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The synthesis, structural characterization, exfoliation, and photophysical studies of two-dimensional (2-D) lanthanide phosphonates, named as Ln(m-pbc); [Ln(m-Hpbc)(m-H2pbc)(H2O)] (Ln = Eu, Tb; m-pbc = 3-phosphonobenzoic acid) based on the phosphonocarboxylate ligand,...

Improvement of the low-cost transition metal electrocatalyst used in sluggish oxygen evolution reaction is a significant but challenging problem. In this study, ultrafine Fe-modulated Ni nanoparticles embedded in a porous Ni-doped carbon matrix were produced by the pyrolysis of zirconium metal-organic-frameworks, in which 2,2′-bipyridine-5,5′-dicarboxylate operating as a ligand can coordinate with Ni2+ and Fe3+. This strategy allows formation of Fe-modulated Ni nanoparticles with a uniform dimension of about 2 nm which can be ascribed to the spatial blocking effect of ZrO2. This unique catalyst displays an efficient oxygen evolution reaction electro-catalytic activity with a low overpotential of 372 mV at 10 mA·cm−2 and a small Tafel slope of 84.4 mV·dec−1 in alkaline media. More importantly, it shows superior durability and structural stability after 43 h in a chronoamperometry test. Meanwhile, it shows excellent cycling stability during 4000 cyclic voltammetry cycles. This research offers a new insight into the construction of uniform nanoscale transition metals and their alloys as highly efficient and durable electrocatalysts.

We report a robust and rigid etb-type metal–organic framework, in which its pore surface is decorated with flexible ethoxyl groups. It shows unprecedentedly selective adsorption of acetone (ETN value of 0.355, kinetic diameter of 4.6 A) over methanol (ETN value of 0.762, kinetic diameter of 3.6 A) for their azeotropic mixture.

Developing feasible ways to achieve tunable gate-opening pressure (Pgo) while minimizing the side effects on the adsorption capacity and enthalpy is greatly desired for flexible MOFs. In this work, we focused on solving this issue by cobalt substitution. We showed the successful modulation of the energy required for the reversible transformation of a soft paddle-wheel so that the whole framework presented a substitution-dependent Pgo for CO2 adsorption.

The problem with metal–organic frameworks (MOFs) as CO2-epoxide cycloaddition catalysts is the ambiguous catalytic sites. No system can precisely modify the structures and thus optimize the catalytic performance. Reticular chemistry is recognized as an efficient approach to systematically control the chemical and structural features as well as the properties of porous, crystalline materials. In this work, a Zn-phosphonocarboxylate framework (ZnPC-2) was employed as a prototype structure to investigate the structure–property relationship (SPR). ZnPC-2 is a porous rutile-type framework constructed by 6-connected Zn3(PO3)2(CO2)4 secondary building unit (Zn3-SBU) and tritopic 5-phosphonobenzene-1,3-dicarboxylic acid (H4pbdc). ZnPC-2 showed the ability to catalyze the CO2 cycloaddition reactions and Zn3-SBU was proved as efficient catalytic site. Guided by reticular chemistry, a series of iso-reticular frameworks, including Hpyr@ZnPC-2 (Hpyr = protonated pyrrolidine, Hpyr is fixed by hydrogen bonding interactions to participate the channel into segments); MZnPC-2 (M = Mg, Mn, Fe, Co, Cu; Zn(II) atoms on Zn3-SBU were partially replaced by M) and ZnPC-2-im (im = imidazole, im coordinates to the apical Zn(II) on Zn3-SBU), were designed and successfully synthesized to explore the precise active site. The catalytic performances over these iso-structures together with density functional theory calculations revealed that the dynamical transformation of the apical Zn (II) on Zn3-SBU from tetrahedral geometry to five coordinated model played the pivotal role during the catalytic process.

Breast cancer is the cancer with the highest incidence all over the world. Phosphatidylinositol 3-kinase is an important regulator of intracellular signaling pathways, which is frequently mutated and overexpressed in majority of human breast cancers, and the inhibition of PI3K has been considered as a promising approach for the treatment of the cancer. Here, we report our design and synthesis of new 7-azaindole derivatives as PI3K inhibitors through the scaffold hopping strategy. By varying the groups at the 3-position of 7-azaindole, we identified a series of potent PI3K inhibitors, whose antiproliferative activities against two human breast cancer MCF-7 and MDA-MB-231 cell lines were evaluated. Representative derivatives FD2054 and FD2078 showed better activity than BKM120 in antiproliferation, reduced the levels of phospho-AKT and induced cell apoptosis. All these results suggested that FD2054 and FD2078 are potent PI3K inhibitors that could be considered as potential candidates for the development of anticancer agents.

Based on indole scaffold, a potent and selective phosphoinositide 3-kinase delta (PI3Kδ) inhibitor, namely FD223, was developed by the bioisosteric replacement drug discovery approach and studied for the treatment of acute myeloid leukemia (AML). In vitro studies revealed that FD223 displays high potency (IC50 = 1 nM) and selectivity (29–51 fold over other PI3K isoforms) against PI3Kδ, and exhibits efficient inhibition of the proliferation of AML cell lines (MOLM-16, HL-60, EOL-1 and KG-1) by suppressing p-AKT Ser473 thus causing G1 phase arrest during the cell cycle. Further given the favorable pharmacokinetic (PK) profiles of FD223, in vivo studies were evaluated using xenograft model in nude mice, confirming its significant antitumor efficacy meanwhile with no observable toxicity. All these results are comparable to the positive group of Idelalisib (CAL-101), indicating that FD223 has potential for further development as a promising PI3Kδ inhibitor for the treatment of leukemia such as AML.

Heteroatom doping and surface modification with oxides are both important strategies to improve the photoelectrochemical (PEC) activities of TiO2 photoelectrodes. However, it is difficult to combine the two strategies into a single synthesis process. Herein, a simple one-pot synthesis method was developed to modify a TiO2 photoelectrode surface by N-doping while simultaneously modifying the surface with In2O3 and NiO. This method involved growing MOF onto a TiO2 surface with N-containing organic ligands and In and Ni salts as metal precursors, followed by heat treatment at 600 °C. The roles of heteroatom doping and oxide modification are proposed as follows. (i) N-Doping extends the absorption edge of the TiO2 to a longer wavelength region and enhances visible light absorption. (ii) N-Doping together with the passivation of TiO2 surface trap states by oxide modification increases the donor density in TiO2. (iii) The generated suitable interfaces on the surface of TiO2 facilitate photogenerated charge separation and transfer. In comparison with the pristine TiO2 photoelectrode, the metal oxide- and heteroatom-modified TiO2 photoelectrode exhibits superior photoelectrochemical performance under both simulated sunlight and visible light illumination. Suitable substrate of the electrode, appropriate size of the as-synthesized MOF precursors, and choice of ligands and metal ions are important factors for this strategy.

Cinnoline is a potential pharmacophore which has rarely been reported for uses as PI3K inhibitors. In this study, a series of cinnoline derivatives were developed as PI3K inhibitors and evaluated for enzymatic and cellular activities. Most compounds displayed nanomolar inhibitory activities against PI3Ks, among which 25 displayed high LLE and micromolar inhibitory potency against three human tumor cell lines (IC50 = 0.264 μM, 2.04 μM, 1.14 μM).

The phosphoinositide 3-kinase (PI3K) inhibitors potently inhibit the signaling pathway of PI3K/AKT/mTOR, which provides a promising new approach for the molecularly targeted cancer therapy. In this work, a novel series of 7-azaindole scaffold derivatives was discovered by the fragment-based growing strategy. The structure-activity relationship profiles identified that the 7-azaindole scaffold derivatives exhibit potent activity against PI3K at molecular and cellular levels as well as cell proliferation in a panel of human tumor cells.

Achieving tailorable gated adsorption by tuning the dynamic behavior of a host porous material is of great interest because of its practical application in gas adsorption and separation. Here we devise a unique cation-exchange approach to tune the dynamic behavior of a flexible anionic framework, [Zn2(bptc)(datrz)]− (denoted as MAC-6, where H4bptc = [1,1′-biphenyl]-3,3′,5,5′-tetracarboxylic acid and Hdatrz = 3,5-diamine-1H-1,2,4-triazole), so as to realize the tailorable gated adsorption. The CO2 adsorption amount at 273 K can be enhanced by exchanging the counterion of protonated dimethylamine (HDMA+) with tetraethylammonium (TEA+), tetrabutylammonium (TBA+), and tetramethylammonium (TMA+), where the adsorption behavior is transferred from nongated to gated adsorption. Interestingly, the Pgo for gate-opening adsorption can be further tuned from 442 to 331 mmHg by simply adjusting the ratio of HDMA+ and TMA+. The origin of this unique tunable property, as revealed by X-ray diffraction experiments and stru...

Heteroatom doping and surface modification with oxides are both important strategies to improve the photoelectrochemical (PEC) activities of TiO2 photoelectrodes. However, it is difficult to combine the two strategies into a single synthesis process. Herein, a simple one-pot synthesis method was developed to modify a TiO2 photoelectrode surface by N-doping while simultaneously modifying the surface with In2O3 and NiO. This method involved growing MOF onto a TiO2 surface with N-containing organic ligands and In and Ni salts as metal precursors, followed by heat treatment at 600 °C. The roles of heteroatom doping and oxide modification are proposed as follows. (i) N-Doping extends the absorption edge of the TiO2 to a longer wavelength region and enhances visible light absorption. (ii) N-Doping together with the passivation of TiO2 surface trap states by oxide modification increases the donor density in TiO2. (iii) The generated suitable interfaces on the surface of TiO2 facilitate photogenerated charge separation and transfer. In comparison with the pristine TiO2 photoelectrode, the metal oxide- and heteroatom-modified TiO2 photoelectrode exhibits superior photoelectrochemical performance under both simulated sunlight and visible light illumination. Suitable substrate of the electrode, appropriate size of the as-synthesized MOF precursors, and choice of ligands and metal ions are important factors for this strategy.

In this paper, UiO-66 nanoparticles have been facilely prepared in a continuous flow microreactor, in which the particle size can be tuned from hundreds to dozens of nanometers by controlling of the residence time. All the products have been completely characterized by FT-IR, PXRD, N 2 sorption, SEM and TEM. Furthermore, NH 2 -functionalized nano-UiO-66 particles have also been prepared and the drug delivery behavior for 5-fluorouracil (5-Fu) was studied in PBS solution.

Metal–organic frameworks with tunable functional groups like solid-solution have received considerable interest. In this paper, a crs-type structure built of [Zn3(OH)(dmtrz)3] triazolate-trinuclear and [Zn2(COO)4] paddlewheel units, linked by 3,5-dimethyl-1,2,4-triazolate (dmtrz) and isophthalate (ipa) ligands (named as MAC-4-A), has been used as a prototype framework. Four types of functional groups (B: 5-hydroxyisophthalate, C: 5-aminoisophthalate, D: 5-ethoxyisophthalate, and E: 5-acetamidoisophthalate) have been integrated into the framework, giving isostructures of MAC-4-B to E, respectively. Then, by the solid-solution framework approach, four group samples are prepared, which are MAC-4-AB-x, MAC-4-AC-x, MAC-4-AD-x, and MAC-4-AE-x (x denoted as the ratio of functional ligands in the framework, x = 0.3, 0.5, 0.7), and their CO2 and N2 adsorptions have been studied. Our results revealed that the CO2 capacity is enhanced with the increase of functional groups and then decreases, showing a maximum uptak...

Two metal–organic frameworks containing a geometrically spin-frustrated trinuclear-triangular copper cluster ([Cu3O]) have been successfully isolated, which are {[Cu4.5(μ3-OH)(dmtrz)3(m-bdc)2.5(H2O)2(CH3OH)(DMF)]·DMF·5H2O}n (MAC-8) and {[Cu5(μ3-OH)(dmtrz)3(bdc)3(H2O)4]·3H2O}n (MAC-9) (Hdmtrz = 3,5-dimethyl-1H-1,2,4-triazole, H2m-bdc = 1,3-benzenedicarboxylic acid, H2bdc = 1,4-benzenedicarboxylic acid, DMF = N′,N-dimethylformamide). Magnetic and gas adsorption studies revealed the successful combination of strong antiferromagnetic properties (Jav = −106.6 and −113.7 cm–1 for [Cu3O] in MAC-8 and MAC-9, respectively) and high surface areas (1058 m2/g for MAC-8 and 1242 m2/g for MAC-9) in both of the structures. Further structural studies revealed that the high surface areas could be ascribed to the unique two-dimensional hexagonal pattern of [Cu3(O)] clusters, in which the [Cu3(O)] clusters are connected to each other in an end-end fashion via mononuclear copper ions/paddle-wheel units.

Two Zn(II)-based metal–organic frameworks, namely, [Zn3(Hbptc)2(DMF)2]·2DMF(1) and [Zn5(bptc)3(H2O)]((CH3)2NH2)2(2), (H4bptc = 3,3′,5,5′-biphenyltetracarboxylic acid, DMF = N,N′-dimethylformamide), have been synthesized using different amounts of nitric acid under mixed-solvothermal conditions. 1 and 2 display different coordination geometries and donor ligands for the Zn2+ ions. In 1, only three carboxylic acid groups of H4bptc take part in the construction of the three-dimensional (3-D) framework with Zn2+, and one remains uncoordinated that can bind to other metal ions. Postsynthetic exchange of 1 with Ln3+ cations demonstrates that 1 can effectively capture metal cations and sensitize the visible-emitting Ln3+.

A flexible structure of {[Zn2(dmtrz)2(L1)]·6H2O}n (MAC-11) (Hdmtrz = 3,5-dimethyl-1H,1,2,4-triazole, H2L1 = (E)-4,4′-stilbenedicarboxylic acid), which is a self-catenated rob-type net built of two-dimensional [Zn(dmtrz)] layers pillared by L1 ligands, has been solvothermally synthesized. It shows an interesting thermo/water-induced reversible phase transformation accompanied by a photoluminescence response from 418 nm to 453 nm. Based on an iso-framework of {[Zn2(dmtrz)2(L2)]·4H2O}n (MAC-13, H2L2 = (E)-azobenzene-4,4′-dicarboxylic acid), a pcu-type framework of {[Zn2(trz)2(L1)]·4H2O}n (MAC-14, Htrz = 1H, 1,2,4-triazole), and a layered structure of [Zn(dmtrz)(HCOO)], a possible mechanism for the photoluminescence response to the reversible phase transformation for MAC-11 was also proposed.

A 7-connected Zn4O unit has been theoretically predicted based on basic zinc acetate [Zn4O(CH3COO)6], which was then experimentally extended into a three-dimensional structure featuring three kinds of nanocage in a unit cell.

An indium phosphonocarboxylate framework, {H3O[In(pbpdc)]·3H2O}n (InPCF-1) (pbpdc = 4'-phosphonobiphenyl-3,5-dicarboxylate), was hydrothermally synthesized. The structure of InPCF-1 features the inorganic chains as rod-shaped second building units. The rod-packing arrangement results in a three-dimensional (3-D) framework with a novel (3,4,5)-connected net. Studies of the gas adsorption, and thermal and chemical stability of InPCF-1 demonstrated its adsorption capacity for CO2, selective separation of CO2 over O2 and N2, high thermal stability, and a remarkable chemical resistance to boiling water, ethyl alcohol, and methylbenzene. Importantly, InPCF-1 shows a selective and sensitive response to Cu(2+) ions. It also serves as a sensor for methylviologen.

Developing photoanodes with efficient visible-light harvesting and excellent charge separation still remains a key challenge in photoelectrochemical water splitting. Here zeolite-type chalcogenide CPM-121 is integrated with TiO2 nanowires to form a heterostructured photoanode, in which crystalline CPM-121 particles serve as a visible light absorber and TiO2 nanowires serve as an electron conductor. Owing to the small band gap of chalcogenides, the hybrid electrode demonstrates obvious absorption in visible-light range. Electrochemical impedance spectroscopy (EIS) shows that electron transport in the hybrid electrode has been significantly facilitated due to the heterojunction formation. A >3-fold increase in photocurrent is observed on the hybrid electrode under visible-light illumination when it is used as a photoanode in a neutral electrolyte without sacrificial agents. This study opens up a new avenue to explore the potential applications of crystalline porous chalcogenide materials for solar-energy co...

A novel phosphonocarboxylic ligand, 4′-phosphonobiphenyl-3,5-dicarboxylic acid (H4pbpdc), was synthesized to construct 4 zinc compounds, namely, {[Zn3(pbpdc)2·2R}n (R = C5H12N for 1, C4H10N for 2 and C6H16N for 3) and {[Zn2pbpdc]·C6H18N3}n(4), which were characterized by X-ray crystallography, elemental analysis, FTIR and TG. Structures 1 ~ 3 have the same 3-dimensional (3-D) frameworks with point symbol of {4.6.73.8}2{42.6.72.8}2{42.62.7.8}2{42.62.72}. Structure 4 is constructed from a 6-connected metallic cluster and 3-connected phosphonocarboxylic building units resulting in a topology of flu-3,6-C2/c. The luminescent properties of compounds 1 ~ 4 and organic ligand were studied.

A three-dimensional porous structure of [Zn7O2(bpdc)4(dmpp)2]·6DEF·10H2O (MAC-7, H2bpdc = 4,4'-biphenyldicarboxylic acid, Hdmpp = 3,5-dimethyl-4-(4'-pyridyl)pyrazole), built of 12-bridged carboxylate-pyrazolate shared Zn7O2 clusters, has been synthesized. Because of the presence of 12-bridged carboxylate-pyrazolate shared building block, MAC-7 is a double-linked pcu-type framework and shows reversible phase transformation. Photoluminescent property studies indicate that MAC-7 could sense nitrobenzene over toluene, p-xylene, and mesitylene by luminescent quenching.

Cyanide group is a robust electron-mediate ligand, widely used in functional coordination polymers. Synthesis of cyanide-containing functional coordination polymersvia solvothermal in situ reaction is a new efficient approach. In this paper, four novel ternary coordination polymers, namely [Ag3(trz)2(CN)]n (1), [Ag3(detrz)2(CN)]n (2), [Ag4(dptrz)2(CN)2]n (3), [Ag3(dptrz)2(CN)]n (4) (Htrz = 1H-1,2,4-triazole, Hdetrz = 3,5-diethyl-1H-1,2,4-triazole, Hdptrz = 3,5-dipropyl-1H-1,2,4-triazole), were solvothermally synthesized and characterized. The cyanide groups are all in situ generated from C–C cleavage reaction of acetonitrile. The cyanide group acts as terminal group in 1, while as linker in 2, 3, 4. Phosphorescent properties of these in situ products are studied and compared with binary silver-triazole coordination polymers. The results show that phosphorescent emissions of 2, 3, and 4 are red-shifted compared to that of 1.

Three isoreticular zinc(II)-phosphonocarboxylate frameworks, namely {[Zn(3)(pbdc)(2)]·2H(3)O}(n) (ZnPC-2), {[Zn(3)(pbdc)(2)]·Hpd·H(3)O·4H(2)O}(n) (Hpd@ZnPC-2) and {[Co(1.5)Zn(1.5)(pbdc)(2)]·2H(3)O}(n) (CoZnPC-2) (H(4)pbdc=5-phosphonobenzene-1,3-dicarboxylic acid, pd=pyrrolidine), were solvothermally synthesized. ZnPC-2 has a 3D structure based on trinuclear Zn(II) clusters (Zn(3)-SBU) showing 3D interconnected channels. Hpd@ZnPC-2 contains an isoreticular framework of ZnPC-2 with small channels blocked by Hpd molecules. In CoZnPC-2, Zn(II) ions in ZnPC-2 are partially substituted by Co(II) ions. The Friedel-Crafts benzylation reactions were carried out over these isoreticular porous materials. The catalytic results reveal that ZnPC-2 is an excellent heterogeneous Lewis acid catalyst with a high selectivity (>90%) towards less bulky para-oriented products. The catalytic reaction has been proved to occur inside the pore of ZnPC-2, and the immobilized Zn(3)-SBUs are the active sites.

Four metal phosphonate hybrid compounds, [Pb(Hpbc)] (1), [Pb3(pbc)2(H2O)2] (2), [Cd(H2pbc)2(H2O)2] (3) and [Cd1.5(pbc)(H2O)1.5] · 0.5H2O (4) (H3pbc = 3-phosphono-benzoic acid) were successfully synthesized by the hydrothermal/solvothermal reaction of metal acetate and 3-phosphono-benzoic acid. Compounds 1–4 were pH-dependent products and characterized by elemental analysis, Fourier transform infrared (FT-IR) spectra and single-crystal X-ray diffraction studies. Compound 1 is a two-dimensional (2D) structure constructed by inorganic layer and organic pendant. With the increase of pH value, structure 2 shows 3D inorganic framework with distributing organic moieties in the channels. In 3, the Cd2O10 dimers are linked by alternating terminal and bridging ligands, resulting in 1D chain structure. Compound 4 is a 2D structure where the 1D inorganic chains are connected by the organic moieties of the ligands.

A highly efficient air-initiated hydrosilylation of unactivated alkynes and alkenes and dehalogenation of halohydrocarbons with tris(trimethylsilyl)silane ((TMS)3SiH) as a reducing agent has been established under solvent-free conditions. These observations demonstrate that the potential and versatility of air to function as a competent initiator for Si–H bond activations. It can rival organic initiators and metal catalysts in its efficiency and is a superior initiating system from economic, environmentally sound and practical perspectives.

The reaction of the osmium–antimony cluster Os3(μ-H)(μ-SbPh2)(μ3,η2-C6H4)(CO)9 with AsPh3 at room temperature afforded the o-phenylene cluster Os3(μ-H)(SbPh2)(μ2,η2-C6H4)(CO)9(AsPh3) by nucleophilic addition via a metal–metal bond cleavage, and the substitution product Os3(μ-H)(SbPh2)(μ3,η2-C6H4)(CO)8(AsPh3). It reacted with tBuNC to afford the adduct Os3(μ-H)(SbPh2)(μ2,η2-C6H4)(CO)9(CNtBu) quantitatively. This adduct isomerised slowly on standing via migration of the isonitrile, while photolysis led to decarbonylation to Os3(μ-H)(SbPh2)(μ2,η2-C6H4)(CO)8(CNtBu). All the products have been characterised completely, including by X-ray crystallography, and their structures exhibit very long Os–Os bonds.

Using structure-directing agents, pore space partitions of a Zn-phosphonocarboxylate framework have been achieved. Selective adsorption of CO(2) over N(2) has been greatly improved from ca. 9 : 1 to 94 : 1.

The reaction of the cluster Os3(μ-SbPh2)(μ-H)(μ3,η2-C6H4)(CO)9, 1, with a number of alkenes and dienes led to cluster condensation to afford the novel cluster Os5(μ4-Sb)(μ-SbPh2)(μ-H)2(μ3,η2-C6H4)(μ,η2-C6H4)(CO)14, 3, as the major product, and another novel cluster Os5(μ4-Sb)(μ-SbPh2)(μ-H)(μ3,η6-C6H4)(CO)14(Ph), 4. Reaction of 3 with the Group 15 ligands EPh3 (E = P, As, Sb) afforded the corresponding monosubstituted derivatives Os5(μ4-Sb)(μ-SbPh2)(μ-H)2(μ3,η2-C6H4)(μ,η2-C6H4)(CO)13(EPh3), 6.

The reaction of the osmium-antimony cluster Os 3 (μ-SbPh2)(μ-H)(μ 3 ,η 2 -C 6 H 4 )(CO) 9 , 1, with the terminal alkynes PhC≡CH and t BuC≡CH led to products involving C-C bond coupling with the phenylene ligand on the cluster, viz., Os 3 (μ-SbPh2)(μ,η 2 -HC=C(H))Ph)(μ-η 4 -C6H4C-(H)CPh)(CO) 7 , 2, and Os 5 (μ 4 -Sb)(μ-SbPh 2 )(μ-H)(μ 3 ,η 3 -C 6 H 4 )(μ,η 2 -PhC=C(H)Bu t )(CO) 1 4 , 4. Cluster 1 was also found to be an effective catalyst for the cyclotrimerization of diphenylacetylene to hexaphenylbenzene.

At ambient temperatures, the reaction of Os 3 (μ-H)(μ-SbPh 2 )(μ 3 ,η 2 -C 6 H 4 )(CO) 9 , 1, with PPh 3 proceeded via a nucleophilic addition product, Os 3 (μ-H)(μ-SbPh 2 )(μ 2 ,η 2 -C6H4)(CO) 9 (PPh 3 ), 2a. This can lose CO to giveOs 3 (μ-H)(μ-SbPh 2 )(μ 3 ,η 2 -C 6 H 4 )(CO) 8 (PPh 3 ), 3a, isomerize, deorthometalate to Os 3 (μ-SbPh 2 )(C 6 H 5 )(CO) 9 (PPh 3 ). 5a, or react with excess PPh 3 to give an orthometalated product, Os 3 (μ-SbPh 2 )(CO) 8 (PPh 2 C 6 H 4 )(PPh 3 ) 2 , 6a. The origin of the orthometalated phenyl ring in 6a has been established via the reaction of a p-tolyl analogue of 2a, viz., Os 3 (μ-H)(μ-SbPh 2 )(μ 2 ,η 2 -C 6 H 4 )(CO) 9 {(p-tolyl) 3 P}, 2b, with PPh 3 .

Three homochiral metal–organic frameworks ( MOF s) based on enantiopure chiral ligand: (R)-2,2’-dimethoxy-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-3,3′-dicarboxylic acid ( H 2 L ), namely Cd( L )(Py) 3 1 , Cu( L )(Py) 3 2 , Na[Cd( L )( LH )] · 2.5H 2 O 3 (Py = pyridine), were firstly synthesized, under solvothermal reactions. X-ray single-crystal diffraction studies reveal that 1 and 2 adopt one-dimensional (1D) infinite helical structures, while 3 possesses 2D chiral framework structure adopting ABAB offset stacking modes along the a -axis. Thermogravimetric analyses ( TGA ) display that 3 is thermally stable to 330 °C which is rare for homochiral MOF s.

Four compounds based on polyoxometalates, [Cu(4-bpo)(H2O)][Cu2(μ2-Cl)(4-bpo)2(H2O)][SiW12O40][N(CH3)4]2·H2O (1), [Cu(4-bpo)]4[P2W18O62][N(CH3)4]2·6H2O (2), [Cu2(μ2-OH)(4-bpo)2(Hina)(H2O)2]2[P2W18O62]·4H2O (3), and [Cu2(Hina)4(H2O)2][H2P2W18O62](Hina)·11H2O (4) (4-bpo=2,5-bis(4-pyridyl)-1,3,4-oxadiazole, ina=isonicotinic acid), have been hydrothermally synthesized and characterized by elemental analysis, IR, and single-crystal X-ray diffraction. The 3-D framework of 1 is composed by Keggin-type polyoxoanions {SiW12} and two types of infinite chains, {Cu(4-bpo)(H2O)}n and {Cu2(μ2-Cl)(4-bpo)2(H2O)}n, through hydrogen bonds. Compound 2 has a 3-D rigid framework which is fabricated by Wells–Dawson type polyoxoanions {P2W18} and Cu-(4-bpo) chains through covalent bonds. Compound 3 contains an infinite {Cu2(μ2-OH)(4-bpo)2(Hina)(H2O)2}n double-chain and {P2W18} polyoxoanions immobilized in the voids between the chains. Compound 4 exhibits a 3-D supramolecular network directed by hydrogen bonds between {P2W18} polyoxoanions and the double paddle-wheel {Cu2(Hina)4(H2O)2}. Compounds 1–4 were tested as heterogeneous catalysts for the epoxidation of styrene using tert-butyl hydroperoxide (TBHP) as oxidant. The compounds show catalytic activity with 2 giving the highest yield of styrene oxide.

A highly efficient air-initiated hydrosilylation of unactivated alkynes and alkenes and dehalogenation of halohydrocarbons with tris(trimethylsilyl)silane ((TMS)3SiH) as a reducing agent has been established under solvent-free conditions. These observations demonstrate that the potential and versatility of air to function as a competent initiator for Si–H bond activations. It can rival organic initiators and metal catalysts in its efficiency and is a superior initiating system from economic, environmentally sound and practical perspectives.

3-Phosphonobenzoic acid (3-H3pbc) was designed as an extended 4-connected ligand to build zeolite-like metal–organic frameworks (ZMOFs). Controlled assembly of Zn2+ with ligand 3-H3pbc results in two distinct structures with zeolitic topologies of MER and RHO, namely [Zn(3-pbc)]·H3O·0.5H2O (1) and Zn2.5(3-pbc)2(H2O)·nS (S represents the disordered solvent molecules) (2), respectively. The framework of 1 consists of double crankshaft chains formed by alternating ZnO4 and O3PC tetrahedra that are cross-linked by 3-pbc to generate a three-dimensional zeolitic open-framework. It is worth noting that structure 2 builds a zeolitic framework in a novel way, which has not been found in other metal phosphonocarboxylates. The organic part of 3-pbc does not participate in the construction of zeolitic topology and only plays a decorative role inside the cages.

A three-dimensional (3D) porous structure of [Cu3(μ3-OH)(μ2-O)(dmtrz)2(HCOO)(μ2-H2O)(H2O)3]·H2O (1) has been in situ solvothermally synthesized. In 1, the trinuclear triangular [Cu3(μ3-OH)(μ2-O)(dmtrz)2] cluster connects itself infinitely, resulting in the type-II channel structure, which is different from that of the rigid type-I channel structure reported previously. Reversible dehydration and rehydration induced crystal-to-amorphous-like phase transformation for structure 1 has been observed and confirmed by PXRD patterns and gas adsorption. Furthermore, as a response to the structural transformation, the stimuli-induced modulation of magnetic properties have been observed.

Two novel zinc phosphonocarboxylates, Zn(3)(pbc)(2)(bpy)(H(2)O)·H(2)O (1) and Zn(2)(pbc)(2)·Zn(bpy)(H(2)O)(4)·2H(2)O (2) (pbc = 4-phosphono-benzoic acid, bpy = 2,2'-bipyridine), were hydrothermally synthesized and structurally characterized. Both of them exhibit zeolitic ABW topology in which double-zigzag inorganic chains are cross-linked by the organic parts. It is notable that the metal complex Zn(bpy)(H(2)O)(x) plays different roles in the two compounds. In 1, the Zn(bpy)(H(2)O) units coordinate with the phosphonate and carboxylate oxygen atoms and participate in the construction of the three-dimensional framework. In 2, the in situ generated [Zn(bpy)(H(2)O)(4)](2+) cation acts as a template, which directs the ABW-type open-framework by strong hydrogen bonds. It is the first example where a metal complex is used as a template in the synthesis of metal phosphonates. The luminescent properties of 1 and 2 are also investigated.

Two novel Zn(II) metal-organic frameworks (MOFs) constructed by trinuclear-triangular and paddle-wheel units, namely {[Zn(5)(dmtrz)(3)(IPA)(3)(OH)]·DMF·H(2)O}(n) (MAC-4, Hdmtrz = 3,5-dimethyl-1H-1,2,4-triazole, H(2)IPA = isophthalic acid, DMF = dimethyl formamide) and {[Zn(5)(dmtrz)(3)(OH-IPA)(3)(OH)]·DMF·5H(2)O}(n) (MAC-4-OH, OH-H(2)IPA = 5-hydroxyisophthalic acid), were solvothermally synthesized. Single-crystal analyses reveal that MAC-4-OH is an iso-reticular framework of MAC-4 with channels functionalized by hydroxyl groups. Gas adsorption reveals that MAC-4-OH shows a significant enhancement for CO(2) uptake compared with that of MAC-4 due to the existence of electrostatic attractive interactions, though its surface area is lower than that of MAC-4.