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Xanthene‐backbone FLPs featuring secondary borane functions −B(ArX)H (where ArX=C6F5 (ArF) or C6Cl5 (ArCl)) have been targeted through reactions of the dihydroboranes Me2S ⋅ BArXH2 with [4,5‐xanth(PR2)Li]2 (R=Ph, iPr), and investigated in the synthesis of related cationic systems via hydride abstraction. The reactivity of these systems (both cationic and charge neutral) with ammonia have been probed, with a view to probing the potential for proton shuttling via N−H bond 'activation.' We find that in the case of four‐coordinate boron systems (cationic or change neutral), the N−H linkage remains intact, supported by a NH⋅⋅⋅P hydrogen bond which is worth up to 17 kcal mol−1 thermodynamically, and enabled by planarization of the flexible xanthene scaffold. For cationic three coordinate systems, N‐to‐P proton transfer is viable, driven by the ability of the boron centre to stabilise the [NH2]− conjugate base through N‐to‐B π bonding. This proton transfer can be shown to be reversible in the presence of excess ammonia, depending on the nature of the B‐bound ArX group. It is viable in the case of C6F5 substituents, but is prevented by the more sterically encumbering and secondary donor‐stabilising capabilities of the C6Cl5 substituent. [ABSTRACT FROM AUTHOR]

Interest is growing in transition metal‐free compounds for small molecule activation and catalysis. We discuss the opportunities arising from synthesizing sodium‐doped amorphous silicon‐boron‐nitride (Na‐doped a‐SiBN). Na+ cations and 3‐fold coordinated BIII moieties were incorporated into an amorphous silicon nitride network via chemical modification of a polysilazane followed by pyrolysis in ammonia (NH3) at 1000 °C. Emphasis is placed on the mechanisms of hydrogen (H2) activation within Na‐doped a‐SiBN structure. This material design approach allows the homogeneous distribution of Na+ and BIII moieties surrounded by SiN4 units contributing to the transformation of the BIII moieties into 4‐fold coordinated geometry upon encountering H2, potentially serving as frustrated Lewis acid (FLA) sites. Exposure to H2 induced formation of frustrated Lewis base (FLB) N−= sites with Na+ as a charge‐compensating cation, resulting in the in situ formation of a frustrated Lewis pair (FLP) motif (≡BFLA⋅⋅⋅Hδ−⋅⋅⋅Hδ+⋅⋅⋅:N−(Na+)=). Reversible H2 adsorption‐desorption behavior with high activation energy for H2 desorption (124 kJ mol−1) suggested the H2 chemisorption on Na‐doped a‐SiBN. These findings highlight a future landscape full of possibilities within our reach, where we anticipate main‐group‐mediated small molecule activation will have an important impact on the design of more efficient catalytic processes and the discovery of new catalytic transformations. [ABSTRACT FROM AUTHOR]

Hydroboranes are versatile reagents in synthetic chemistry, but their synthesis relies on energy‐intensive processes. Herein, we report a new method for the preparation of hydroboranes from hydrogen and the corresponding haloboranes. Triethylamine (NEt3) form with dialkylchloroboranes a Frustrated Lewis Pair (FLP) able to split H2 and afford the desired hydroborane with ammonium salts. Unreactive haloboranes were unlocked using a catalytic amount of Cy2BCl, enabling the synthesis of commonly used hydroboranes such as pinacolborane or catecholborane. The mechanisms of these reactions have been examined by DFT studies, highlighting the importance of the base selection. Finally, the system‘s robustness has been evaluated in one‐pot B−Cl hydrogenolysis/hydroboration reactions of C=C unsaturated bonds. [ABSTRACT FROM AUTHOR]

This work reports the cooperative reactivity of rare‐earth aryloxide complexes with N‐heterocyclic carbene (NHC) or N‐heterocyclic olefin (NHO), showcasing their synergistic effect on the activation of H2 and diverse organic substrates. Reactions of RE(OAr)3 (RE=La, Sm, and Y; Ar=2,6‐tBu2−C6H3) with unsaturated NHC ItBu (:C[N(R)CH]2, R=tBu) isolated abnormally bound RE metal NHC complexes RE/aNHC. In contrast, no metal‐NHO adducts were formed when RE(OAr)3 were treated with NHO (R2C=C[N(R)C(R)]2, R=CH3). Both RE/aNHC and RE/NHO Lewis pairs enabled cooperative H2 activation. Furthermore, RE(OAr)3 were found to catalyze the hydrogenation of the exocyclic C=C double bond of NHO under mild conditions. Moreover, treatment of the La/aNHC complex with benzaldehyde produced a La/C4 1,2‐addition product. The La/NHO Lewis pair could react with (trimethylsilyl)diazomethane and α, β‐conjugated imine, affording an isocyanotrimethylsilyl lanthanum amide complex and a La/C 1,4‐addition product, respectively. [ABSTRACT FROM AUTHOR]

Porous frustrated Lewis pairs (FLPs) have been demonstrated as cutting‐edge heterogeneous catalysts in acidic–basic catalysis, which, yet faces great challenges in synthesis. Herein, we propose a one‐step de novo assembly strategy for constructing porous FLPs by capping monodentate ionic liquids (ILs) on metal clusters during the synthesis of metal–organic frameworks (MOFs). The capping of ILs makes adjacent metal sites on MOFs transforming to coordinatively‐unsaturated metal Lewis acids, producing FLPs containing Lewis basic Cl− ions from ILs and metal sites. The distribution of ILs on the framework of MOFs endows the catalysts with large surface areas (up to 2125 m2 g−1), open channels and good stability. The porous FLPs behave unprecedented activity for atmospheric CO2 activation and coupling with epoxides (25–40°C, 1 bar, without cocatalyst). This de novo assembly strategy exhibits good universality for synthesizing porous FLPs from different kinds of ILs, paving a facile approach for designing high‐efficiency acidic–basic catalysts. [ABSTRACT FROM AUTHOR]

The study investigates the reactivity of a cyclic five‐membered intramolecular P/B frustrated Lewis pair towards acrolein through a cycloaddition reaction. Intrinsic reaction coordinate (IRC) calculations suggest the single‐step mechanism. It has been observed that the cycloaddition reaction occurs through a concerted mechanism in both the presence and absence of the catalyst. Analysis of reaction force and reaction electronic flux provides valuable information about the total work required and electronic activity along the IRC. Additionally, natural bonding orbital (NBO) analyses enrich the understanding of the mechanism in terms of the electron transfer process during the chemical reaction. [ABSTRACT FROM AUTHOR]

A method of desymmetrization of geminal difluoroalkanes using frustrated Lewis pair (FLP) mediated monoselective C–F activation where a chiral sulfide is the Lewis base component is reported. The stereoselective reaction provides generally high yields of diastereomeric sulfonium salts with dr of up to 95:5. The distribution of diastereomers is found to be thermodynamically controlled via facile sulfide exchange. The use of enantiopure chiral sulfides allows for high stereospecificity in nucleophilic substitution reactions and the formation of stereoenriched products. [ABSTRACT FROM AUTHOR]

Abstract A method of desymmetrization of geminal difluoroalkanes using frustrated Lewis pair (FLP) mediated monoselective C–F activation where a chiral sulfide is the Lewis base component is reported. The stereoselective reaction provides generally high yields of diastereomeric sulfonium salts with dr of up to 95:5. The distribution of diastereomers is found to be thermodynamically controlled via facile sulfide exchange. The use of enantiopure chiral sulfides allows for high stereospecificity in nucleophilic substitution reactions and the formation of stereoenriched products.

The reaction of seventeen borane derivatives of five-membered N-heterocyclic rings (BNHRs) with CO2 has been studied by means of DFT calculations. Several non-covalent complexes between the BNHRs and CO2 which evolve through a TS in a single adduct for each BNHR have been identified. The calculated IRC of the TS has allowed to identify the non-covalent complex involved in the reaction in each case. The stationary points of the reactions have been analyzed with the distortion/interaction partition model. In addition, empirical models have been attempted to correlate the acid (fluoride ion affinity) and basic (proton affinity) properties of the isolated BNHR with the TS barriers and adduct energies. The energetics of the reactions are influenced by the number of nitrogen atoms in the ring. [ABSTRACT FROM AUTHOR]

The reaction of seventeen borane derivatives of five-membered N-heterocyclic rings (BNHRs) with CO2 has been studied by means of DFT calculations. Several non-covalent complexes between the BNHRs and CO2 which evolve through a TS in a single adduct for each BNHR have been identified. The calculated IRC of the TS has allowed to identify the non-covalent complex involved in the reaction in each case. The stationary points of the reactions have been analyzed with the distortion/interaction partition model. In addition, empirical models have been attempted to correlate the acid (fluoride ion affinity) and basic (proton affinity) properties of the isolated BNHR with the TS barriers and adduct energies. The energetics of the reactions are influenced by the number of nitrogen atoms in the ring. [ABSTRACT FROM AUTHOR]

Lewis pair polymerization (LPP) has demonstrated its unique advantages, such as high activity, high stability, and adjustable variability, towards the polymerization of (meth)acrylate monomers in comparison with the other polymerization techniques. The combination of Lewis acid (LA) and Lewis base (LB) to construct Lewis pairs (LPs) with appropriate Lewis basicity, Lewis acidity, and steric effects would significantly impact the polymerization process, including chain initiation, propagation, termination and chain transfer reaction, as well as polymerization manner of monomers. In this feature article, we briefly review recent progress made by our research group towards the living/controlled polymerization of (meth)acrylate monomers, which were accomplished by a series of newly designed LPs, including monofunctional LPs, dual-initiating LPs and intramolecular tethered trifunctional LP. This article is divided into three parts: (1) the development of monofunctional living/controlled LP polymerization system; (2) the design and preparation of dual-initiating LPs in synthesizing thermoplastic elastomers; (3) the application of intramolecular trifunctional LP to the synthesis of cyclic polymers. These developed LPPs have demonstrated their powerful capability in precise control over the molecular weight, molecular weight distribution, and monomer sequence as well as the topology of polymers. This review will serve as a good resource or guideline for researchers currently working in the area of LPP and for those who are interested in synthesizing new materials by LPP. [ABSTRACT FROM AUTHOR]

We present a strategy for the union of N‐allylamines and carbonyl compounds by the concerted action of B(C6F5)3 and a N‐based Brønsted base under redox‐neutral conditions. The reaction of in situ generated conjugated iminium ions and enolates affords δ‐aminocarbonyl compounds without waste generation. Furthermore, we describe that the cooperative action of B(C6F5)3, a chiral Zn‐based complex, and an amine facilitates the stereoselective reaction of a glycinate Schiff base ester and an N‐allylamine to afford an α‐substituted α‐amino ester. [ABSTRACT FROM AUTHOR]

CO2 hydrogenation to methane is gaining increasing interest as one of the most promising ways to store intermittent renewable energy in the form of chemical fuels. Ni particles supported on CeO2 represent a highly efficient, stable and inexpensive catalyst for this reaction. Herein, Ni‐doped CeO2 nanoparticles were tested for CO2 methanation showing an extremely high Ni mass‐specific activity and CH4 selectivity. Operando characterization reveals that this performance is tightly associated with ionic Νi and Ce3+ surface sites, while formation of metallic Ni does not seem to considerably promote the reaction. Theoretical calculations confirmed the stability of interstitial ionic Ni sites on ceria surfaces and highlighted the role of Ce‐O frustrated Lewis pair (FLP), Ni‐O classical Lewis pair (CLP) and Ni‐Ce pair sites to the activation of H2 and CO2 molecules. To a large extent, the theoretical predictions were validated by in situ spectroscopy under H2 and CO2 : H2 gaseous environments. [ABSTRACT FROM AUTHOR]

The first polyoxometalates (POMs) composed of MoIV, MoV2, discrete d1‐MoV and MoVI, [MoIV3MoV6MoVI4O32(μ2‐OH)(μ3‐OH)py9] (1), was prepared from the solvothermal partial oxidation of [MoIV3O2(O2CCH3)6(H2O)3]ZnCl4 in a mixture of pyridine and water. The MoV=O adduct‐free unit [H2Mo12O33py9] presents the 11e‐reduced Mo derivative of the paratungtic archetype. The use of methanol, ethanol, n‐propyl alcohol and triglycol instead of water produced the isostructural [MoIV3MoV6MoVI4O32(μ3‐OH)(μ2‐OR)py9](R=CH3, 2; C2H5, 3; C3H7, 4; C2H4OH, 5), providing the first examples of MoIV3−POMs containing bridging alkoxyl groups. The addition of [CrIIIMo6O24]9− led to the substitution of {MoV=O}3+ with {CrIII‐py}3+ in the allomer [MoIV3MoV5MoVI4CrIIIO32(μ‐OH)2py10] (6). Using a mixture of Mo3 and MoW2 precursors afforded WVI‐incorporated allomer [MoIV3MoV6MoVIWVI3O32(μ‐OH)2py9] (7). The complete substitution of MoVI with WVI by using a mixture of the Mo2W, MoW2 and W3 precursors produced the diamagnetic [MoIV3MoV6WVI4O33(μ3‐OH)py9]− (syn‐8) resulting from the anti→syn conversion between the top and bottom M3 triads concomitant with MoV‐MoV bonding. Both anti‐1‐7 and syn‐8 have been characterized by X‐ray single crystal structural analyses. The spin distribution and magnetic interactions have been investigated by temperature‐dependent magnetic susceptibility and DFT theoretical calculations. Heterogeneous hydrogen transfer catalysis has been examined by the Lewis catalysis field (LCF) theory. [ABSTRACT FROM AUTHOR]

We present convenient syntheses of a range of PNP‐type phosphines which feature a pair of ortho‐functionalized ArPPh2 moieties linked via a central NMe unit, but which differ in the nature of the additional backbone 'tether' linking the aryl groups. These comprise the acyclic system bis(2‐diphenylphosphinophenyl)methylamine, together with related systems centred around 5‐, 6‐ and 7‐membered heterocycles. Structurally, contraction of the backbone tether causes the phosphine centres to be projected further apart, and to be more constrained torsionally to the plane containing the NMe unit. In terms of potential frustrated Lewis pair (FLP) reactivity, the conformationally more flexible systems based on an acyclic linker or a cyclic core featuring a 7‐membered ring, are capable of achieving P−B bond formation and generating a classical Lewis adduct with B(C6F5)3. The less flexible carbazole‐derived compound (featuring a five membered heterocyclic core) gives rise to an FLP at room temperature, and an equilibrium mixture of frustrated and classical Lewis pairs at lower temperatures. Most interestingly, the PNP system based on a central six‐membered acridine ring ‐ which gives rise to the shortest contacts in the solid state between phosphorus and the N‐bound methyl group – undergoes C−H activation in the presence of B(C6F5)3, resulting in the formation of B−H and P−C bonds. [ABSTRACT FROM AUTHOR]

To overcome the thermodynamic and kinetic impediments of the Sabatier CO2 methanation reaction, the process must be operated under very high temperature and pressure conditions, to obtain an industrially viable conversion, rate, and selectivity. Herein, we report that these technologically relevant performance metrics have been achieved under much milder conditions using solar rather than thermal energy, where the methanation reaction is enabled by a novel nickel‐boron nitride catalyst. In this regard, an in situ generated HOB⋅⋅⋅B surface frustrated Lewis's pair is considered responsible for the high Sabatier conversion 87.68 %, reaction rate 2.03 mol gNi−1h−1, and near 100 % selectivity, realized under ambient pressure conditions. This discovery bodes well for an opto‐chemical engineering strategy aimed at the development and implementation of a sustainable 'Solar Sabatier' methanation process. [ABSTRACT FROM AUTHOR]

Synthesising ammonia at low temperature and catalyst with high stability, selectivity and activity other than Haber Bosch process and enzymatic process is still a challenging task for chemists. Computational studies serve as a valuable tool for testing novel ideas in order to either realise a theoretically viable and practicably synthesizable catalyst or to identify more of the recognised catalysts both of which are important for the growth of this field. In this report, DFT calculations have been performed on a hypothetical Fe‐ imidazolyl‐pyridine complex to explore the potential of dinitrogen reduction to ammonia at optimum temperature and pressure using Fe bound Nitrogen as a catalyst and FLP‐H2 as a co‐catalyst. FLP acts as a hydrogen source which prevents the binding of H2 with metal centre. The computed Gibbs free energies of the elementary reactions revealed that the Fe bound nitrogen can act as a catalyst for activating and functionalising dinitrogen to yield NH3 and N2H2. [ABSTRACT FROM AUTHOR]

High substrate conversion and special hydrogenation regioselectivity of α, β-unsaturated carbonyl compounds were achieved through rigid confined space in frustrated Lewis pair/MOF catalyst. [Display omitted] • A novel catalyst was constructed by frustrated Lewis pair immobilizing in MOF. • It showed excellent regioselectivity for α,β-unsaturated carbonyl reduction. • The steric hindrance and reaction mechanism were illuminated by the DFT method. The regioselective hydrogenation of α, β-unsaturated carbonyl compounds is an extremely important transformation. However, its development is hampered by a lack of precise and efficient catalysts. In this work, triggered by the steric hindrance and confinement capacity of the catalyst, we designed a novel catalyst FLP/MIL-101(Cr), with the bulky frustrated Lewis pair (FLP) of PPh 3 and B(C 6 F 5) 3 immobilized in NH 2 -MIL-101(Cr). In the well-tailored FLP/MIL-101(Cr), the promoted selective reduction behaviors were realized, with cinnamyl alcohol selectivity up to 99 % and the complete substrate conversion in cinnamyl aldehyde reduction. Experimental characterizations and theoretical calculations indicated that the C N bond and π-π stacking interaction between FLP and the organic ligand of MIL-101(Cr) implemented and reinforced a rigid structure. Compared with homogeneous FLP, the special nano-space in FLP/MIL-101(Cr) catalyst benefits the selective reduction behavior towards the unsaturated bond with the smaller steric hindrance in α,β-unsaturated carbonyl compounds. As expected, FLP/MIL-101(Cr) showed good stabilities of skeleton structure and catalytic performance. This contribution provides an ingenious strategy to design FLP heterogeneous catalysts and represents its utilization possibility in selective reduction. [ABSTRACT FROM AUTHOR]

The incorporation of transition metals into frustrated Lewis pairs (FLPs) offers multiple opportunities for bond activation and catalysis. In this work, we explore the combination of the Lewis acidic Ir(III) cation [(η5‐C5Me5)IrCl(PMe2ArDipp2)]+ (ArDipp2=C6H3−2,6‐(C6H3−2,6‐iPr2)2) with the Lewis basic Pt(0) compound Pt(PtBu3)2. The bulkiness of the phosphine ligands prevents the formation of a bimetallic adduct. We have explored the cooperative cleavage of dihydrogen to gauge bimetallic FLP reactivity. As anticipated, compounds [(η5‐C5Me5)Ir(Cl)(H)(PMe2ArDipp2)] and [PtH(PtBu3)2]+ are rapidly formed, which suggests an actual FLP mechanism operating. However, our in‐depth experimental/computational study evidences that the whole process is considerably more complicated. Instead of a genuine FLP‐type activation, we favor a synergistic route that entails a number of equilibrium processes and the Brønsted catalyzed hydrogenation of the Pt(0) precursor. [ABSTRACT FROM AUTHOR]

Practical application of direct methanol fuel cell (DMFC) technology is greatly hindered by the strong dependence of anodic methanol oxidation reaction (MOR) on precious Pt based catalyst and the unsatisfying performance of Pt. Therefore, increasing the utilization and the catalytic performance of Pt toward MOR in DMFC is urgent. Here in this work, CeO 2 is modified via a plasma-phosphating combing strategy and is invited as Frustrated Lewis Pair to assist the catalytic MOR process on Pt sites. Simultaneously, the plasma-phosphating combing strategy leads to negatively charged sites on CeO 2 surface, which can be functioned as host for Pt anchoring, facilitating the even dispersion of Pt nanocrystals. Besides, this strategy also has an effect on the Ce3+/Ce4+ ratio and vacancy oxygen ratio on CeO 2 surface, which are critical to the adsorbed OH generation and anti-CO poisoning ability, thus boosting the MOR catalytic activity of Pt. DMFC device therefore exhibits ca. 30% maximum power density enhancement compared with the commercial Pt/C based DMFC. Ce–P LFP, which is highly active toward water dissociation reaction, is constructed in CeO 2 substrate via the plasma-phosphating combing strategy for Pt loading and the MOR activity is significantly improved with the DMFC performance enhanced by 30%. [Display omitted] • Ce–P LFP is constructed substrate via the plasma-phosphating combing strategy. • Pt nanoparticles can be evenly distributed on Ce–P LFP rich CeO 2 substrate. • DMFC performance is enhanced by ca. 30%. [ABSTRACT FROM AUTHOR]

A series of different aryl‐linked (frustrated) Lewis pairs with perfluoroethylsilyl and ‐stannyl functions as Lewis acids has been prepared. The 1,2‐phenylene linked tin/phosphorus Lewis pair with a di‐tert‐butylphosphanyl unit as base shows a strong intramolecular donor‐acceptor interaction, but still readily adds hydrogen chloride. At the same time, the analogous silicon/phosphorus Lewis pair could not be obtained due to the decomposition of at least one perfluoroethyl group. With a sterically more demanding 2,2,6,6‐tetramethylpiperidine base, stable Lewis pairs could be obtained for both, silicon and tin. However, they do not show activity in small molecule activation with H2, phenyl isocyanate, CS2 or SO2. Furthermore, 2‐benzyl‐linked tin/nitrogen and silicon/phosphorus Lewis pairs were synthesized. Studies on their reactions towards small molecules did not show any reactivity, probably caused by an unfavorable preorganization due to rotation of the benzyl position. [ABSTRACT FROM AUTHOR]

The development and application of new organoboron reagents as Lewis acids in synthesis and metal-free catalysis have dramatically expanded over the past 20 years. In this context, we will show the recent uses of the simple and relatively weak Lewis acid BPh3—discovered 100 years ago—as a metal-free catalyst for various organic transformations. The first part will highlight catalytic applications in polymer synthesis such as the copolymerization of epoxides with CO2, isocyanate, and organic anhydrides to various polycarbonate copolymers and controlled diblock copolymers as well as alternating polyurethanes. This is followed by a discussion of BPh3 as a Lewis acid component in the frustrated Lewis pair (FLP) mediated cleavage of hydrogen and hydrogenation catalysis. In addition, BPh3-catalyzed reductive N-methylations and C-methylations with CO2 and silane to value-added organic products will be covered as well along with BPh3-catalyzed cycloadditions and insertion reactions. Collectively, this mini-review showcases the underexplored potential of commercially available BPh3 in metal-free catalysis. [ABSTRACT FROM AUTHOR]

Asymmetric hydrogenation, a seminal strategy for the synthesis of chiral molecules, remains largely unmet in terms of activation by non‐metal sites of heterogeneous catalysts. Herein, as demonstrated by combined computational and experimental studies, we present a general strategy for integrating rationally designed molecular chiral frustrated Lewis pair (CFLP) with porous metal–organic framework (MOF) to construct the catalyst CFLP@MOF that can efficiently promote the asymmetric hydrogenation in a heterogeneous manner, which for the first time extends the concept of chiral frustrated Lewis pair from homogeneous system to heterogeneous catalysis. Significantly, the developed CFLP@MOF, inherits the merits of both homogeneous and heterogeneous catalysts, with high activity/enantio‐selectivity and excellent recyclability/regenerability. Our work not only advances CFLP@MOF as a new platform for heterogeneous asymmetric hydrogenation, but also opens a new avenue for the design and preparation of advanced catalysts for asymmetric catalysis. [ABSTRACT FROM AUTHOR]

The chemical conversion of CO2 to long‐chain chemicals is considered as a highly attractive method to produce value‐added organics, while the underlying reaction mechanism remains unclear. By constructing surface vacancy‐cluster‐mediated solid frustrated Lewis pairs (FLPs), the 100 % atom‐economical, efficient chemical conversion of CO2 to dimethyl carbonate (DMC) was realized. By taking CeO2 as a model system, we illustrate that FLP sites can efficiently accelerate the coupling and conversion of key intermediates. As demonstrated, CeO2 with rich FLP sites shows improved reaction activity and achieves a high yield of DMC up to 15.3 mmol g−1. In addition, by means of synchrotron radiation in situ diffuse reflectance infrared Fourier‐transform spectroscopy, combined with density functional theory calculations, the reaction mechanism on the FLP site was investigated systematically and in‐depth, providing pioneering insights into the underlying pathway for CO2 chemical conversion to long‐chain chemicals. [ABSTRACT FROM AUTHOR]

The reactivity towards Si−H and Sn−H bonds of a dimethylxanthene‐based frustrated Lewis pair featuring −PiPr2 and −B(C6F5)2 functions in the 4‐, and 5‐positions is reported. In the case of silanes, greater steric bulk appears to impede reactivity, with only PhSiH3 and SiH4 showing unambiguous evidence for Si−H bond activation. In the case of PhSiH3, the silylphosphonium borohydride 1iPr(SiH2Ph)(H) is formed by Si−H bond activation across the P/B manifold. 1iPr(SiH2Ph)(H) loses PhSiH3 in hydrocarbon solution and therefore can only be crystallized from the neat silane. On heating, it undergoes a metathesis process leading to installation of the −SiH2Ph function at the 5‐position of the xanthene scaffold, with accompanying migration of the boryl group (as Piers' borane, HB(C6F5)2) to the phosphine. Similar chemistry is observed with SiH4 (although occurring much more readily), and such processes are thought to be mechanistically similar to related rearrangements occurring with the boranes HBpin and HBcat. By contrast, the activation of the weaker Sn−H bonds found in stannanes occurs more readily, even for bulkier substrates, and the stannyl‐phosphonium borohydrides 1iPr(SnnBu3)(H) and 1iPr(SnPh3)(H) are obtained from the room temperature reactions with nBu3SnH and Ph3SnH, respectively. [ABSTRACT FROM AUTHOR]

Olefin–borane π‐complexes have been postulated as intermediates for the addition of frustrated Lewis pairs (FLP) to olefins. In the present study, we have employed this weak interaction to modulate the electronic properties of boron‐based π‐electron materials. A series of donor–π–acceptor (D–π–A) fluorophores that contain an alkenyl‐bridged diarylboryl group is synthesized. A crystallographic analysis revealed that the olefin and boron moieties are held in close proximity. Upon addition of a Lewis base to a solution of these D–π–A fluorophores, an FLP‐type addition occurs with concurrent significant changes in the absorption and emission properties. The FLP‐type reaction shifts the reaction site from the Lewis‐acidic boron atom to a carbocationic center, and thereby even facilitates a reaction with bulky Lewis bases. For example, a tricyclohexylphosphine adduct thus generated exhibits temperature‐dependent reversible dissociation/association behavior. These results provide a design strategy for stimuli‐responsive emissive boron‐based materials. [ABSTRACT FROM AUTHOR]

The trapping reactions of carbene analogs G14F2 (G14 = group 14 element) by the benzene‐bridged B/P‐Rea frustrated Lewis pair (FLPs) molecule are studied using density functional theory (B3LYP‐D3(BJ)/def2‐TZVP). Our theoretical investigations predict that only the CF2 intermediate rather than other heavy carbene analogs can be trapped by the B/P‐Rea FLP‐type molecule. Energy decomposition analysis‐natural orbitals for chemical valence (EDA‐NOCV) analyses indicate that the bonding nature of the G14F2 catching reactions by the B/P‐Rea FLP‐type molecule is a donor–acceptor (singlet–singlet) interaction rather than an electron‐sharing (triplet–triplet) interaction. Moreover, EDA‐NOCV and frontier molecular orbital (FMO) theory findings strongly suggest that the lone pair (LP) (P) → vacant p–π‐orbital (G14F2) interaction rather than the empty σ‐orbital (B) ← sp2‐σ‐orbital (G14F2) interaction plays a predominant role in establishing its bonding condition during the G14F2 trapping reaction with the B/P‐Rea FLP‐associated molecule. Our activation strain model findings reveal that the atomic radius of the G14 element of G14F2 plays a key role in determining the activation barrier of the G14F2 trapping reactions by the benzene‐bridged B/P‐Rea FLP. The valence bond state correlation diagram (VBSCD) model developed by Shaik is used to rationalize the calculated results. The VBSCD findings demonstrate that in the present trapping reactions, the singlet triplet splitting of G14F2 plays a significant role in influencing its reaction barrier and reaction enthalpy. Our theoretical results demonstrate that the relationship between the geometrical parameters of the transition states and the corresponding reaction free energy barriers agrees well with the findings based on the Hammond postulate. [ABSTRACT FROM AUTHOR]

Molybdenum(VI) bis(imido) complexes [Mo(NtBu)2(LR)2] (R=H 1 a; R=CF31 b) combined with B(C6F5)3 (1 a/B(C6F5)3, 1 b/B(C6F5)3) exhibit a frustrated Lewis pair (FLP) character that can heterolytically split H−H, Si−H and O−H bonds. Cleavage of H2 and Et3SiH affords ion pairs [Mo(NtBu)(NHtBu)(LR)2][HB(C6F5)3] (R=H 2 a; R=CF32 b) composed of a Mo(VI) amido imido cation and a hydridoborate anion, while reaction with H2O leads to [Mo(NtBu)(NHtBu)(LR)2][(HO)B(C6F5)3] (R=H 3 a; R=CF33 b). Ion pairs 2 a and 2 b are catalysts for the hydrosilylation of aldehydes with triethylsilane, with 2 b being more active than 2 a. Mechanistic elucidation revealed insertion of the aldehyde into the B−H bond of [HB(C6F5)3]−. We were able to isolate and fully characterize, including by single‐crystal X‐ray diffraction analysis, the inserted products Mo(NtBu)(NHtBu)(LR)2][{PhCH2O}B(C6F5)3] (R=H 4 a; R=CF34 b). Catalysis occurs at [HB(C6F5)3]− while [Mo(NtBu)(NHtBu)(LR)2]+ (R=H or CF3) act as the cationic counterions. However, the striking difference in reactivity gives ample evidence that molybdenum cations behave as weakly coordinating cations (WCC). [ABSTRACT FROM AUTHOR]

A frustrated Lewis pair‐catalyzed hydroboration of aromatic and aliphatic nitriles was developed. The catalyst provides the primary amines in high yields of 77–99% with catalyst loading as low as 2 mol%. The reaction displays high functional group tolerance towards esters, amides, nitro groups and aliphatic halides. The addition of the diborylated amines to ethyl 3‐phenylpropiolate proceeds with Z‐selectivity with d.r. of >99:1 in 77–90% yield over two steps. The reaction mechanism was investigated by control and computational experiments. [ABSTRACT FROM AUTHOR]

Frustrated Lewis pairs (FLPs) have evolved from a revolutionary concept to widely applied catalysts. We recently reported the ring-expanded N-heterocyclic carbene supported copper(I) boryliminomethanide, (6-Dipp)CuC(=NtBu)Bpin and noted it reacted with heterocumulenes in a fashion reminiscent of FLPs. We thus set out to explore its reactivity with a range of other substrates known to react with FLPs. This was undertaken by a series of synthetic studies using NMR spectroscopy, mass spectrometry, IR spectroscopy, and single crystal X-ray crystallography. (6-Dipp)CuC(=NtBu)Bpin was investigated for its reactivity towards water, hydrogen, and phenylacetylene. Its solution stability was also explored. Upon heating, (6-Dipp)CuC(=NtBu)Bpin decomposed to (6-Dipp)CuCN, which was characterised by SC-XRD and NMR spectroscopy, and pinBtBu. Although no reaction was observed with hydrogen, (6-Dipp)CuC(=NtBu)Bpin reacted with water to form (6-Dipp)CuC(=N(H)tBu)B(OH)pin, which was structurally characterised. In contrast to its FLP-reminiscent heterolytic cleavage reactivity towards water, (6-Dipp)CuC(=NtBu)Bpin acted as a Brønsted base towards phenyl acetylene generating (6-Dipp)CuCCPh, which was characterised by SC-XRD, IR, and NMR spectroscopy, and HC(=NtBu)Bpin [ABSTRACT FROM AUTHOR]

Heteroaryl boronic acids and esters are extremely important and valuable intermediates because of their wide application in the synthesis of marketed drugs and bioactive compounds. Over the last couple of decades, the construction of highly important heteroaryl carbon‐boron bonds has created huge attention. The transition‐metal‐free protocols are more green, less sensitive to air and moisture, and also economically advantageous over the transition‐metal‐based protocols. The transition‐metal‐free C−H borylation of heteroarenes and C−X (X=halogen) borylation of heteroaryl halides represents an excellent approach for their synthesis. Also, various cyclization and alkyne activation protocols have been recently established for their synthesis. The goal of this review article is to summarize the existing literature and the current state of the art for transition‐metal‐free synthesis of heteroaryl boronic acid and esters. [ABSTRACT FROM AUTHOR]

In recent years, borane-based frustrated Lewis pairs have proved to be efficient hydrogenation catalysts and they have become an alternative to transition-metal-based systems. The hydrogen activation by classic FLPs leads to a protonated Lewis base and a borohydride. Consequently, hydrogenations catalyzed by classic FLPs consist of stepwise hydride transfer reactions and protonations (or vice versa). More recently, systems that operate via an initial hydroboration have allowed the substrate scope for FLP-catalyzed hydrogenations to be extended. In this review, hydrogenations of organic substrates catalyzed by borane--based frustrated Lewis pairs are discussed. Emphasis is given to the mechanistic aspects of these catalytic reactions. 1 Introduction 2 FLP-Catalyzed Hydrogenation of Polarized Double Bonds 2.1 Hydrogenation of Michael Acceptors by FLPs 2.2 Asymmetric Hydrogenation of Polarized Double Bonds 2.3 Hydrogenation of Arenes and N-Heterocycles 3 Hydrogenation of Unactivated Olefins and Alkynes 3.1 Hydrogenation of Olefins and Alkynes by an Initial Hydroboration 4 Summary and Outlook [ABSTRACT FROM AUTHOR]

The burgeoning field of frustrated Lewis pair (FLP) heterogeneous catalysts has garnered significant interest in recent years, primarily due to their inherent ability to activate H-source molecules, such as H2, thereby facilitating hydrogenation reactions. However, the application of single metal atom catalysts incorporating FLP sites has been relatively under-explored. In this study, non-precious transition metal atoms were anchored onto a C2N framework with an intrinsic cavity and a defective N-C sheet. Theoretical calculations substantiated energy barriers as low as 0.10 eV for isopropanol activation, thereby positioning these catalysts as highly promising candidates for catalytic transfer hydrogenation of furfural. Electronic structure analyses revealed that the H-O bond breakage in isopropanol molecules was significantly facilitated by the presence of FLP sites within the catalysts. Notably, both Ni-C2N and Ni-N6-C demonstrated exceptional potential as selective catalysts for the hydrogenation of furfural into furfuryl alcohol, exhibiting remarkably low barriers of only 0.65-0.72 eV for the rate-determining steps, which are notably lower than those observed in many traditional catalysts. Theoretical investigations strongly imply that the construction of single atom catalysts with FLP sites could significantly enhance the activity and selectivity for hydrogenation reactions, thus stimulating the experimental synthesis of such catalysts., (© 2024 Wiley‐VCH GmbH.)

Gas molecules, as a family of unique polyatomic building blocks, have long been considered hard to involve in molecular assembly or construct assembled materials due to their structural simplicity yet paucity of defined interacting sites. To solve this non-trivial challenge, a core idea is to break the limit of current ways of bonding gas molecules, endowing them with new modes of interactions that match the basic requirements of molecular assembly. In recent years, a new concept, named the dynamic gas-bridged bond (DGB), has emerged, which allows for gas molecules to constitute a dynamic bridging structure between other building blocks with the aid of frustrated Lewis pairs. This makes it possible to harness gas in a supramolecular or dynamic manner. Herein, this perspective discusses distinct dynamic natures of DGBs and manifests their particular functions in various fields, including the control of molecular/polymeric self-assembly nanostructures, creation of multidimensional assembled materials, and recyclable catalysts. The future research direction and challenges of dynamic gas-bridged chemistry toward gas-programmed self-assembly and gas-constructed adaptive materials are highlighted.

This study employs computational methods to investigate the mechanism of H 2 activation by frustrated Lewis pair (FLP) species, including both intermolecular and intramolecular nitrothane/borane FLP systems. Previous studies have proposed two qualitative reactivity mechanism models to explain the facile cleavage of H 2 by FLPs. The findings of this study support the electric field mechanism as the favorable pathway for H 2 cleavage. Utilizing frontier molecular orbital theory and energy decomposition analysis, the study explores the electronic structure and nature of the reactions under an external electric field (EEF). Analysis using the activation strain model highlights the significant influence of geometrical deformation energies of FLPs on the activation barriers of H 2 activation reactions. Computational results suggest that H 2 activation by FLP molecules follows the electric field mechanism, indicating the potential of the FLP/EEF combination as an effective activator for inert molecules., (© 2024 Wiley-VCH GmbH.)

Zeolites have found tremendous applications in the chemical industry. However, the dynamic nature of their active sites under the flow of adsorbate molecules for adsorption and catalysis is unclear, especially in operando conditions, which could be different from the as‐synthesized structures. In the present study, we report a structural transformation of the adsorptive active sites in SAPO‐34 zeolite by using acetone as a probe molecule under various temperatures. The combination of solid‐state nuclear magnetic resonance, in situ variable‐temperature synchrotron X‐ray diffraction, and in situ diffuse‐reflectance infrared Fourier‐transform spectroscopy allow a clear identification and quantification that the chemisorption of acetone can convert the classical Brønsted acid site adsorption mode to an induced Frustrated Lewis Pairs adsorption mode at increasing temperatures. Such facile conversion is also supported by the calculations of ab‐initio molecular‐dynamics simulations. This work sheds new light on the importance of the dynamic structural alteration of active sites in zeolites with adsorbates at elevated temperatures. [ABSTRACT FROM AUTHOR]

The metal‐free catalytic hydrogenolysis of silyl triflates and halides (I, Br) to hydrosilanes is unlocked by using arylborane Lewis acids as catalysts. In the presence of a nitrogen base, the catalyst acts as a Frustrated Lewis Pair (FLP) able to split H2 and generate a boron hydride intermediate capable of reducing (pseudo)halosilanes. This metal‐free organocatalytic system is competitive with metal‐based catalysts and enables the formation of a variety of hydrosilanes at room temperature in high yields (>85 %) under a low pressure of H2 (≤10 bar). [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Olefins are very easily accessible compounds which are both popular substrates in synthetic chemistry and good ligands in the organometallic complexes. This dual character makes olefins a rich source of chiral ligands and catalysts for asymmetric catalysis. Herein, we will briefly summarize our studies on the development of chiral diene ligands for transition‐metal catalyzed asymmetric reactions and chiral FLP catalysts for asymmetric metal‐free hydrogenations and hydrosilylations. Several acyclic chiral diene ligands as well as P/olefin and S/olefin hybrid ligands were developed for Rh or Pd‐catalyzed asymmetric reactions. With these ligands in hand, we further put forward a novel strategy for acquiring chiral FLP catalysts via the in situ hydroboration of chiral dienes with Piers' borane. These catalysts proved to be highly effective for asymmetric metal‐free hydrogenations and hydrosilylations of imines, silyl enol ethers, ketones, and aromatic N‐heterocycles. What is the most favorite and original chemistry developed in your research group? The development of acyclic dienes both as chiral ligands and as precursors of chiral FLP catalysts. How do you get into this specific field? Could you please share some experiences with our readers? When I started my independent research in 2008, chiral olefins belong to one novel ligand type. We got into the field with the thought of the simpler the better. This experience further led us to step into FLP catalysis. What is the most important personality for scientific research? Courage and persistence of doing something unique. What are your hobbies? Walking and playing cards. How do you keep balance between research and family? Life is not only research, but also family. You believe it, the balance is there. What is your favorite journal(s)? My favorite journal is Organic Letters, in which authors can publish their work rapidly and readers can browse the progress of organic chemistry comprehensively. [ABSTRACT FROM AUTHOR]

We successfully synthesized BiOClBr-OV nanoflowers with oxygen vacancies and Br substitutional defects. Under visible light irradiation, the double defects exhibit a synergistic enhancement effect on the photocatalytic reduction of CO 2 and outstanding electron storage capacity. The high photocatalytic performance of BiOClBr-OV is attributed to the three-in-one combination of adsorption sites, FLP active sites, and electron storage sites. Finally, the catalytic mechanism and possible reaction pathways are thoroughly explained through in-situ DRIFTS and DFT calculations. This work provides a new multi-sites unified catalyst design strategy, providing deep insight into the photocatalytic reduction of CO 2 and making the application of Bi-based semiconductors in round-the-clock photocatalysis possible. [Display omitted] • The BiOClBr-OV opens the door to round-the-clock photocatalytic reduction of CO 2. • The photocatalytic activity and electron storage capacity of BiOClBr-OV are 6.8 and 34.2 times higher than those of pristine BiOCl. • BiOClBr-OV achieves the three-in-one combination of adsorption sites, FLP active sites, and electron storage sites. • The photocatalytic mechanism and possible reaction pathways of BiOClBr-OV systematically clarified by the DFT calculations and in-situ characterization techniques. In recent years, the production of high-value solar fuels through photocatalytic reduction of CO 2 has received significant attention. However, the low photocatalytic activity and intermittent nature of solar light contributing to low production rates have hindered its large-scale application. This study successfully constructed BiOClBr-OV with two defects (Cl/Br substitution, oxygen vacancy), which not only enhanced the catalytic activity but also opened the door to round-the-clock photocatalytic reduction of CO 2. Under visible light exposure, the double defects exhibit a synergistic enhancement effect and outstanding electron storage capacity, resulting in 6.8 times and 34.2 times increase in the photocatalytic activity and electron storage capacity, respectively, compared to the pristine BiOCl. Additionally, BiOClBr-OV with surface oxygen defects exhibits frustrated Lewis pair (FLP) catalytic behavior, effectively changing the adsorption mode of CO 2 and enhancing its activation ability. Simultaneously, the unsaturated surface Bi ions of BiOClBr-OV are the electron storage centers, achieving the three-in-one combination of adsorption sites, FLP active sites, and electron storage sites, leading to excellent photocatalytic activity. Finally, the catalytic mechanism and possible reaction pathways are thoroughly explained through in-situ technologies and density functional theory (DFT) calculations. This work introduces a novel multi-sites unified catalyst design strategy, providing deep insight into the photocatalytic CO 2 reduction process and making the application of Bi-based semiconductors in round-the-clock photocatalysis possible. [ABSTRACT FROM AUTHOR]

[Display omitted] • Low H 2 dissociation barrier is obtained using N, S-doped Co single atom catalyst (Co-N 3 SN-def1); • Frustrated Lewis pair comprised of Co and pyridinic N sites facilitate the H 2 dissociation; • H transfer via the solvent water is the main diffusion pathway; • Moderate H adsorption strength at pyridinic N site contributes to the low breaking barrier of N-O bond in nitrobenzene. The limitation of isolated metal active sites in single atom catalysts (SAC) hinder their application in hydrogenation reactions, necessitating the creation of additional active site beyond the metal site. This study introduces pyridinic N and S atoms into the N/C sheet, optimally adjusting the local environment of the Co site. This adjustment synergistically enhances H 2 activation, H diffusion, and promotes the hydrogenation of nitrobenzene into aniline. The sterically hindered Co acidic site and N basic site, known as frustrated Lewis pairs, in defect-containing Co-N 3 SN-def1 model cooperatively facilitate the highly efficient cleavage of the H 2 molecule with a barrier of only 0.37 eV. The findings suggest that the pyridinic N site in the Co-N 3 SN-def1 model acts as a reservoir for *H, significantly contributing to the enhanced activity for the hydrogenation of nitrobenzene. The mechanism unveiled in this study offers valuable insights for designing efficient heterogeneous catalysts for target hydrogenation reactions. [ABSTRACT FROM AUTHOR]

The frustrated Lewis pair (FLP) concept in homogeneous catalysis was extended to heterogeneous catalysis via the supramolecular system of FLP between deprotonated zeolite framework oxygens and confined carbocations in methanol‐to‐olefin (MTO) reactions. In this FLP, the polymethylbenzenium (PMB+) functioned as the Lewis acid to accept an electron pair, and the deprotonated framework oxygen site acted as the Lewis base to donate an electron pair. This FLP theoretically demonstrated the ability to undergo H2 heterolysis and alkanes dehydrogenation, and this was further confirmed by gas chromatography–mass spectrometer (GC‐MS) catalytic experiments inside FLP‐containing chabazite zeolites. All these findings not only bring new recognition to the carbocation chemistry in zeolite cages but also put forward a new reaction pathway as one part of MTO reactions. [ABSTRACT FROM AUTHOR]

The development of chiral borane Lewis acid catalysts opened the door for transition-metal-free catalyzed asymmetric organic reactions. Herein, we have summarized our work on the preparation of two classes of novel chiral bicyclic bisborane Lewis acid catalysts derived from C 2-symmetric [3.3.0] dienes and [4.4] dienes, respectively. These catalysts not only form frustrated Lewis pairs with Lewis bases to catalyze asymmetric hydrogenation reactions but also activate Lewis basic functional groups in traditional Lewis acid catalyzed asymmetric reactions. 1 Introduction 2 Synthesis of C 2-Symmetric Fused Bicyclic Bisborane Catalysts and Their Use in Imine Hydrogenation 3 Synthesis of Spiro Bicyclic Bisborane Catalysts and Their Use in -N -Heteroarene Reduction 4 Other Types of Asymmetric Reactions Promoted by Chiral -Bicyclic Bisborane Catalysts 5 Conclusion [ABSTRACT FROM AUTHOR]

The chemistry of dicationic diboranes with two BII atoms that are engaged in direct B−B bonding is by enlarge unexplored, although these molecules have intriguing properties due to their combined Lewis acidic and electron‐donor properties. Unsymmetric dicationic diboranes are extremely rare, but especially attractive due to their polarized B−B bond. In this work we report the directed synthesis of several stable unsymmetric dicationic diboranes by reaction between the electron‐rich ditriflato‐diborane B2(hpp)2(OTf)2 (hpp=1,3,4,6,7,8‐hexahydro‐2H‐pyrimido[1,2‐α]pyrimidinate) and phosphino‐pyridines, establishing B−N and B−P bonds with the diborane concomitant with triflate elimination. In the case of 2‐((ditertbutylphosphino)methyl)pyridine, the B−N bond is formed instantly, but the B−P bond formation requires (due to steric constraints) several days at ambient conditions for completion, creating an intermediate that could be used for frustrated Lewis pair (FLP)‐like chemistry. Here we test its reaction with an aldehyde, and propose a new type of FLP‐like chemistry. [ABSTRACT FROM AUTHOR]

The activation of the C-F bond in 1-fluorobutane, 1, 1-difluorobutane and 1, 1, 1-trifluorobutane by some frustrated Lewis pair (FLP) has been assessed by DFT based computational study. The FLPs are constructed from lutidine Lewis base in association with either B(C6F5)3 or Al(C6F5)3. Thermodynamics and kinetics of the reactions are studied, which reveals the concerning bond activation mediated by the Al(C6F5)3/lutidine FLP is more favourable than the analogous reactions mediated by the B(C6F5)3/lutidine pair. Therefore, the Al(C6F5)3 acid is superior to the B(C6F5)3 acid to construct an effective FLP for some unusual bond activation. The EDA-NOCV study together with the WBI calculation reveals the C-F bond activation in the studied systems takes place by the cooperative action of the FLP partners. The activation strain model reveals the strain energy of the reactants to reach the transition state (TS) rather than the interaction energy at the TS is the decisive factor to the TS barrier height of the concerned reactions. The activation of C-F bond in 1-fluorobutane, 1, 1-difluorobutane and 1, 1, 1-trifluorobutane by B(C6F5)3/lutidine and Al(C6F5)3/lutidine pairs has been assessed computationally. The Al(C6F5)3/lutidine pair is superior to the B(C6F5)3/lutidine pairs for such unusual bond activation as revealed by this study. [ABSTRACT FROM AUTHOR]

New naphtho[2,1,8,7-klmn]xanthene and benzo[kl]xanthene-based intramolecular phosphane–borane frustrated Lewis pairs (FLPs) were investigated in catalyzed H2 activation and CO2 hydrogenation processes. According to DFT predictions at the B3LYP-D3 level, the presence of rigid scaffolds and increased P···B distances in the investigated FLPs lead to a remarkable drop in the energy barrier for CO2 hydrogenation (by up to 19.2 kcal mol−1, compared to the parent dimethylxanthene-based FLP). Furthermore, the energy differences between the transition states for H2 activation and CO2 hydrogenation are significantly reduced, making both processes feasible under relatively mild experimental conditions.

Supramolecular polymers, which are chain-like aggregates of monomers connected by noncovalent interactions, possess some unique chemical and physical properties and functions. In the past thirty years, great achievements have been made in the field of supramolecular polymers. So far, there are some critical issues in this research field, including the development of the driving forces and design strategies for supramolecular polymerization, and supramolecular building blocks and functions of supramolecular polymers. Recently, for the first time, Meijer et al in Eindhoven University of Technology and Yamaguchi et al in Nagoya University incorporated the frustrated Lewis pair (FLP) into the design of supramolecular polymers. By developing FLP building blocks based on planar triarylborane and triarylamine, the supramolecular polymers were constructed based on noncovalent interactions of B−N coordination, and these polymers exhibited the unique fluorescence properties with the long lifetime and circularly polarized nature. Furthermore, Yamaguchi et al disclosed a novel supramolecular polymerization method through the design of the double-trap metastable state enabled by intramolecular hydrogen bonds and intermolecular B−N coordination, achieving dynamic and controllable supramolecular polymerization. These studies thus developed new driving forces and building blocks for supramolecular polymerization, and also provided novel design strategies for supramolecular polymerization and new functions of supramolecular polymers. [ABSTRACT FROM AUTHOR]

The frustrated Lewis pair (FLP) derived from 2,6‐lutidine and B(C6F5)3 is shown to mediate the catalytic hydrogenation of CO2 using H2 as the reductant and a silylhalide as an oxophile. The nature of the products can be controlled with the judicious selection of the silylhalide and the solvent. In this fashion, this metal‐free catalysis affords avenues to the selective formation of the disilylacetal (R3SiOCH2OSiR3), methoxysilane (R3SiOCH3), methyliodide (CH3I) and methane (CH4) under mild conditions. DFT studies illuminate the complexities of the mechanism and account for the observed selectivity. [ABSTRACT FROM AUTHOR]

The diphenylphosphinites [(THF)Li(OPPh2)]4 and [(THF)2Be(OPPh2)2] have been synthesized via direct deprotonation of diphenylphosphine oxide with nBuLi and BePh2, respectively, as well as via salt metathesis. These compounds were characterized by multinuclear NMR spectroscopy, and the side-products of the reactions obtained under various reaction conditions have been identified. The beryllium derivative could not be isolated and decomposed into diphosphine oxide Ph2PP(O)Ph2. The solid-state structure of this final product together with that of [(THF)Li(OPPh2)]4 have been determined by single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]