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Alkylamines with different chain lengths including n-butylamine, n-hexylamine, and n-octylamine, are applied to regulate the CsPbIBr2 perovskite film quality by strain engineering. The status of residual strains is controllably modulated, resulting in improved efficiency and stability of carbon-based hole-transport-material free CsPbIBr2 perovskite solar cells. [ABSTRACT FROM AUTHOR]

The production of N,N-dialkyl arylamines is relevant for a range of high-value materials such as pharmaceuticals, agrochemicals and organic materials. In general, these molecules are assembled via multiple pre-functionalization steps of the aromatic compound and a subsequent cross-coupling with the arylamine under harsh conditions. In this manuscript, we develop a more sustainable and efficient method for the direct C–H amination of arenes and alkylamines using Ru(bipy)32+ entrapped in the supercages of a faujasite support (CBV-100). This creates a heterogeneous photocatalyst that can be used under visible light irradiation. Furthermore, the mesomeric and/or inductive effects of the substituent groups on the arene coupling partner are thoroughly investigated using Hammett plots, leading to a rationally guided solvent selection (HFIP or CH3CN). Using reduced reaction temperatures (<0 °C) drastically improves the product yield, while suppressing the generation of side products. [ABSTRACT FROM AUTHOR]

A practical method for regioselective hydroarylation of unactivated γ- or δ-vinyl alkylamines has been reported, enabling facile preparation of highly value-added ε- or ζ-aryl alkylamines. The protocol employs nickel catalysis, shows high functional group tolerance and can be used for modifying bio-related molecules. [ABSTRACT FROM AUTHOR]

We herein present an example of photoinduced catalyst- and metal-free allylic defluorinative alkylation of trifluoromethyl alkenes with Katritzky salts in the presence of an easily available Hantzsch ester or Et3N. This simple method can accommodate primary alkylamines with primary and secondary carbon, delivering gem-difluoroalkenes with complex and diverse structures. In addition to the sustainable feature of being catalyst- and metal-free, the transformations also show great functional group tolerance and viable functionalization of late-stage biologically and pharmaceutically relevant molecules. [ABSTRACT FROM AUTHOR]

The aminolysis of five-membered cyclic carbonates, which results in polyhydroxyurethanes (PHUs), is one of the most promising synthetic pathways to achieve isocyanate-free polyurethanes (NIPUs), one of the main industrial challenges over the coming years. This study highlights the higher reactivity of β-hydroxylamines toward cyclic carbonates compared to classical alkylamines through the determination of their reaction rate constants. The key role of the β-OH substituent in the aminolysis was revealed by DFT investigation. Polyfunctional alkylamine and β-hydroxyamine were then used for the synthesis of fully biobased PHU thermosets. The higher reactivity of β-hydroxylamines was confirmed by the gelation time gap between the two formulations studied. After curing, the thermal and thermo-mechanical properties of the thermosets were compared. [ABSTRACT FROM AUTHOR]

Six new 3D isomorphous lanthanide metal organic frameworks (Ln-MOFs), [Ln2(L)2(DMF)2(H2O)4]·H2O·DMF (Ln = Pr (1); Sm (2); Eu (3); Gd (4); Dy (5); Ho (6)); H3L = 5-(2-nitro-4-carboxylphenyl)isophthalic acid, have been solvothermally synthesized and characterized. Crystallographic studies revealed that these MOFs were isomorphous 3D frameworks in which the dinuclear units with double (μ-COO)2 bridges were interlinked by the L ligands. They represent the (3,6)-connected (42·6)(43·68·82·10·12) topology. The magnetic coupling through double carboxylate bridges is antiferromagnetic in Pr-MOF (1), Gd-MOF (4), Dy-MOF (5) and Ho-MOF (6). Furthermore, Dy-MOF (5) shows slow magnetic relaxation behaviors under zero dc field. The luminescence sensing experiments demonstrated that Eu-MOF (3) displayed highly selective, well-recyclable properties and a low detection limit for sensing alkylamines in water systems. The study of Ln-MOF sensing for alkylamines is very scarce. [ABSTRACT FROM AUTHOR]

In the presence of a substoichiometric amount of a tert-butoxy radical precursor, the reaction of alkylamines with sulfonylarenes was found to give α-arylated alkylamines through homolytic aromatic substitution, where a radical chain is operative. [ABSTRACT FROM AUTHOR]

We have found that a series of N-(5-bromosalicylidene) alkylamines exhibited distinct chromic behaviour depending on the parity of their alkyl chain length. A group with an even number of carbon atoms in the alkyl chain showed photochromism, while another group with odd number showed thermochromism. [ABSTRACT FROM AUTHOR]

Crystalline layered silicates are promising materials for the rational design of innovative catalysts owing to their wide variety and easily tunable surfaces. However, diffusional limitation in their interlayer spaces limits their catalytic efficiency. Herein, we have developed a novel synthesis route to a highly active layered silicate catalyst utilizing Hiroshima University Silicates (HUSs). We attempted to tune the stacking structure of the silicate layers of HUS-2 and HUS-7 ion-exchanged with hexadecyltrimethylammonium (C16TMA) using organic-solvent treatment, and found that cyclohexane treatment of HUS-7 gave an aggregate of randomly restacked silicate nanosheets without degradation of the original silicate framework. We prepared amine-modified base catalysts by grafting with aminopropyltriethoxysilane, and investigated their catalytic performances in the transesterification of triacetin with methanol. The catalyst based on HUS-7 exhibited a much higher catalytic activity than that based on HUS-2 despite their similar framework topology. Moreover, the activity of the HUS-7-based catalyst was far superior to those of other base catalysts, such as amine-modified mesoporous silica, catalyst resin, and alkylamine. Detailed characterization of the catalysts revealed that the improved accessibility of reactant molecules to the immobilized functional units, which is derived from both the randomly stacked silicate layers and the bulky interlayer molecules incorporated, is the primary reason for the high catalytic efficiency of the layered silicate catalyst. [ABSTRACT FROM AUTHOR]

The postsynthetically created electron-deficient 2,2′-bipyridinium moieties in a Zr-MOF provide charge-transfer interacting sites for recognizing and capturing alkylamines with excellent selectivity; meanwhile the MOF shows fast and reversible vapochromism and luminescence quenching in response to alkyamines. [ABSTRACT FROM AUTHOR]

A green method for epoxidation of imines using an environmentally benign oxidant system, H2O2/dimethyl carbonate, was developed. N-Alkyloxaziridines were prepared in high yields from N-alkylamines and (hetero)aromatic aldehydes in one-pot fashion, whereas N-sulfonyloxaziridines have been prepared by using the same oxidant system and 5 mol% of Zn(OAc)2·2H2O as catalyst. [ABSTRACT FROM AUTHOR]

Reaction-based, sensitive sensing of aldehyde and ketone gases in real time was effectively achieved on QCM chips thin-coated with silver ionic liquids SIL 1 and SIL 4, respectively. The method platform developed in this work involves straightforward synthesis of functional silver ionic liquids in water, and is label-free and highly chemoselective with superior gas reactivity for SIL 1 and SIL 4 and, most significantly, totally insensitive to moisture. [ABSTRACT FROM AUTHOR]

The effect of styryl imide substitution on optical and electrochemical properties of core-substituted naphthalenediimides was examined by synthesizing a series of naphthalenediimide molecules. 2-Ethylhexylamino and 5-(2-ethylhexyl)thiophene groups were used as core substituents. The optical and electrochemical properties of styryl imide substituted compounds were compared with other imide substitutions including hydrogen, 2-ethylhexyl, and 4-thienylphenyl. Generally, the imide substituents had little effect on the optical properties, except when the combination of alkylamino core and styryl imide substituents was used. In this latter case, we observed a 104 nm red-shift of the absorption onset upon film formation, resulting in an unusually broad visible absorption (500–800 nm) for these types of molecules. This is explained by the planarity of the molecule and the formation of intermolecular aromatic donor–acceptor type interactions. These results show that imide substituents play a role in tuning opto-electronic properties of NDI molecules, and that NDI molecules with styryl imide substituents merit further evaluation for opto-electronic applications. [ABSTRACT FROM AUTHOR]

Hydrophobic monofunctionalized cucurbit[7]uril derivatives (1 and 2) were synthesized by clicking CB[7]-azide with propargylated alkylamines. Compounds 1 and 2 form self-inclusion complexes that are transformed into vesicle-type assemblies by addition of guests (3–5) as confirmed by 1H and DOSY NMR, SEM, TEM, and fluorescence spectroscopy. [ABSTRACT FROM AUTHOR]

Switchable-hydrophilicity solvents (SHSs) are solvents that can switch reversibly between one form that is miscible with water to another that forms a biphasic mixture with water. For these SHSs, we use CO2 at 1 bar as a stimulus for triggering the transformation to the water-miscible form and removal of CO2 to achieve the reverse. We now report the identification of 13 new SHSs, including the first secondary amine SHSs, and a comparison of all known SHSs in terms of safety and environmental impacts. Amines which include another functional group, especially oxygen-containing groups, are less hazardous than alkylamines. Secondary amines can have improved switching speeds relative to tertiary amines. The variety of SHSs identified suggests that amine SHSs can be designed to have ideal properties for a given application. [ABSTRACT FROM AUTHOR]

In this work, alkylamine–polyol assemblies were used as “micro-reactors” for in situ preparation of gold nanoparticles, which in turn altered the gel structure and morphology significantly. [ABSTRACT FROM AUTHOR]

A detailed study of the transamination reaction between Ti(NMe2)4 and primary amines RNH2 is reported Alkylamines (1-adamantylamine, t-butylamine) and triphenylsilylamine yield dimers of the type [Ti(μ-NR)(NMe2)2]2 (R = 1-adamantyl (1), tBu (2), SiPh3 (3)). The experimental conditions and the nature of the amine are important issues that determine the scope and yield of the reaction. When reacted under the same conditions, aniline PhNH2 does not yield the expected dimer, but instead the trimer [Ti3(μ2-NPh)3(μ3-NPh)(NMe2)4(NHMe2)] (5) and tetramer [Ti4(μ-NPh)5(NMe2)6] (6) complexes were characterized. The reaction of Ti(NMe2)4 and 2,6-diisopropylaniline (Ar*NH2) is essentially an equilibrium reaction of great complexity in which multiple species can coexist in solution. However, under certain circumstances, we were able to isolate and/or characterize several new complexes such as [Ti(μ-NAr*)(NMe2)2]2 (7), [(Me2N)2Ti(μ-NAr*)2Ti(NMe2)(NHAr*)] (8), [Ti(NMe2)3]2(μ-NAr*) (9), [(Ar*NH)2Ti(μ-NAr*)2Ti(NMe2)2] (10), [(Me2N)(Me2NH)Ti(μ-NAr*)2Ti(NMe2)(=NAr*)] (11), Ti(NHAr*)4 (12), and [(Ar*NH)2Ti(μ-NAr*)2Ti(NMe2)(NHAr*)] (13). Complexes 8 and 11 are tautomers. Alternatively, complex 7 was prepared by deprotonation of NHMe2 ligands in Ti(=NAr*)Cl2(NHMe2)2 with KN(SiMe3)2. Addition of pyridine (py) to the reaction of Ti(NMe2)4/Ar*NH2 mixtures or to 7 or 8 allows characterization of transient [Ti(μ-NAr*)(NMe2)2]2·py (14) and trapping of the intermediates [(Me2N)(py)2Ti(μ-NAr*)2Ti(NMe2)(=NAr*)] (15), Ti(=NAr*)(NHAr*)(NMe2)(py)2 (16), and Ti(=NAr*)(NHAr*)2(py)2 (17). The crystal structures of 15 compounds were determined by X-ray diffraction studies. [ABSTRACT FROM AUTHOR]

The protonation of 2-pyridylalkylamines (PAA) was investigated through quantum chemical calculations at a DFT level of theory in dichloromethane solution. Two different PAA–H+ species and a dynamic equilibrium between protonated forms were evidenced. The overall geometry of the PAA–H+ promoters is strongly influenced by the nature of the moiety and the absolute configuration of the pseudobenzylic stereocenter. Thus, PAA–H+ complexes were used as organocatalysts in the enantioselective hydroxyalkylation of indole derivatives. The combination of PAA, a strong acid and a soft counter-ion was found to be a mandatory parameter to achieve high yields and selectivities allowing hydroxyalkylation of both N–H and N-protected indoles using a unique catalytic system. [ABSTRACT FROM AUTHOR]

The traditional concept of the synthesis of semiconductor nanocrystals (NCs) by solvent routes usually performed under high temperatures, causes the semiconductor materials to nucleate and grow into various shaped NCs in solution. Therefore, these methods are named as “solvent-thermal approachs”. In this work, we describe a simple and reproducible strategy for the synthesis of PbS NCs at temperatures even as low as −20 °C by using frozen and solidified precursors. With the aid of alkylamines, nano-sized PbS could also nucleate and grow at such low temperatures within a short time (a few seconds). The experimental results not only break people's traditional thinking but also provide a significant and novel direction in the engineering of the synthesis of NCs. In addition, we further systematically investigated the effect of two types of temperatures (the mixing temperature of the precursors and the ripening temperature of the PbS NCs). Combining this with different alkylamines, we found an obvious competition between a growth kinetic process caused by the alkylamines and a thermodynamic process induced by the temperature, which formed variously shaped monodispersed PbS NCs, including flower-, star-, sphere-, truncated octahedron-, cuboctahedron-, quasi cube-, cube-shaped and some hollow PbS NCs. Furthermore, this competition process could also provide a facile and cost-effective route to synthesize size-tunable but shape-permanent PbS NCs and their self-assembly superlattices in the same reaction systems, which is still a major challenge at present. Afterward, both the formation mechanisms of the PbS nanostructures synthesized below room temperature and the shape transformation depending on two types of temperature and alkylamines are systematically discussed. [ABSTRACT FROM AUTHOR]

In the presence of the [Cp*IrCl2]2/NaOH system, the direct N-alkylation of 2-aminoquinazolines and 2-aminopyrimidines with alcohols afforded the N-exosubstituted 2-(N-alkylamino)quinazolines and 2-(N-alkylamino)pyrimidines with 71–96% yields and complete regioselectivities. The protocol is highly attractive because of easily available starting materials, high atom efficiency and environmental friendliness. [ABSTRACT FROM AUTHOR]

Supramolecular hybrid materials of graphene oxide (GO) with octadecylamine or dodecylamine have been fabricated by a simple self-assembly technique at room temperature. Many characterization methods have been used to research the micelle-like nanostructures. Compared to unmodified GO, the alkyl-functionalized graphene hybrids could be easily dispersed in various nonpolar organic solvents, such as petroleum ether, n-heptane, isooctane, dimethylbenzene etc., rather than in polar solvents. It was found that alkylamine plays a key role during such preparation. Octadecanol (ODO) produced hardly any modification of GO under the conditions, because the so-called product (GO-ODO) exhibits a high degree of similarity to GO in solvent dispersion behaviour and the Fourier transform infrared spectroscopy. The addition of alkylamine significantly improves the thermal stability of the nanomaterials. The improved thermal degradation temperatures can be obtained for polyethylene glycol and polymethyl methacrylate after filling it with as little as 1 wt% of the hybrid, suggesting their great potential as novel nanofillers in industry. [ABSTRACT FROM AUTHOR]

This report describes the gold-catalyzed synthesis of fused polycyclic indoles from substituted 2-(1H-indol-1-yl) alkylamines and alkynoic acids in water under microwave irradiation. This protocol proceeds in high atom economy and leads to the generation of two rings, together with the formation of one new C–C bond and two new C–N bonds in a single operation. The advantages of the method include a short reaction time, excellent yield, easy work-up, and the use of microwave irradiation and an environmentally benign solvent. [ABSTRACT FROM AUTHOR]

An insoluble solid of historic Prussian blue (PB) was transformed into dispersible PB nanoparticles in water and various hydrophilic and hydrophobic organic solvents. Via hybrid surface modification using Na4[FeII(CN)6] and short-chain alkylamines, the insoluble PB was successfully dispersed in hydrophilic-and-hydrophobic boundary alcohols, such as n-butanol. The n-butanol-dispersible PB nanoparticles afforded homogeneous spin-coated thin films on various substrates. The chemisorbed shorter-chain alkylamines, n-propylamines, of the PB nanoparticles were thermally released at 100 °C from their surfaces to present stubborn electrochromic PB thin films adhering to the substrate via mutual coordination-bonding networks. [ABSTRACT FROM AUTHOR]

The substituted hydroxylamines, CH3N(H)OH (N-methylhydroxylamine) and (CH3)2NOH (N,N-dimethylhydroxylamine), disproportionate catalytically to the corresponding alkylamines and oxidation products, only in the presence of [Fe(CN)5H2O]3-. Substitution kinetic measurements suggest an initial coordination step to Fe(II). Two parallel N- and O-coordination modes are considered with the subsequent formation of Fe(III), free aminyl (RNCH3) and nitroxide (RN(CH3)O) radicals (R = H, CH3). With CH3N(H)OH, bound nitrosomethane, CH3NO, has been characterized by UV-visible and IR spectroscopies. The mechanism is discussed on the basis of common and differential features with respect to the disproportionation of hydroxylamine catalyzed by the same Fe-fragment. [ABSTRACT FROM AUTHOR]

Consecutive intramolecular desymmetrization and kinetic resolution of 2-substituted N-phenoxycarbonylserinols have been achieved in one-pot by a single chiral catalyst, bisox(7)–CuCl2, to form oxazolidinones with remarkable enantioselectivities (94–99% ee) as tert-alkylamine building blocks. The process culminates in a dual-function of the chiral catalyst. [ABSTRACT FROM AUTHOR]

A facile method for the synthesis of highly fluorinated reduced graphene oxide from graphene oxide using BF3-OEt2 solution and alkylthiol/alkylamine on the Gram scale has been described using a detailed mechanism. The maximum fluorination was as high as 38 wt% and the fluorinated reduced graphene oxide produced has great wettability and high insulating properties. [ABSTRACT FROM AUTHOR]

The enantioselective organocatalytic reduction of trifluoromethyl aryl and alkyl ketoimines afforded the corresponding fluorinated amines with high chemical and stereochemical efficiency. The Lewis base catalyzed reaction with trichlorosilane led to chiral products with a trifluoromethyl group directly linked to the newly generated stereocenter typically in ＞90% yield and up to 98% e.e. [ABSTRACT FROM AUTHOR]

Rh(iii)-catalyzed aromatic C–H amination of acetophenone o-methyloximes with primary N-chloroalkylamines was developed, and the arylamine products were obtained in up to 92% yield. The reaction probably involves rate-limiting electrophilic C–H bond cleavage (kH/kD = 2). [ABSTRACT FROM AUTHOR]

The article offers information on intermolecular hydroamination of monosubstituted allenes with secondary alkylamines catalyzed by platinum (II) and silver derivative. It mentions the effective diastereoselectivity of reactants with catalyst. It further mentions the use of nuclear magnetic resonance spectroscopy analysis for determining the stereochemistry of the purified reaction mixture.

Thin layers of alkylamine-stabilized molybdenum vanadium complex oxide were prepared under hydrothermal condition; these materials exhibited 10-60 times higher catalytic activities than pure crystalline Mo-V-O oxide in the selective oxidation of alcohols. [ABSTRACT FROM AUTHOR]