Chiral nanoporous metal-organic frameworks are constructed by using dicarboxyl-functionalized chiral Ni(salen) and Co(salen) ligands. The Co(salen)-based framework is shown to be an efficient and recyclable heterogeneous catalyst for hydrolytic kinetic resolution (HKR) of racemic epoxides with up to 99.5% ee. The MOF structure brings Co(salen) units into a highly dense arrangement and close proximity that enhances bimetallic cooperative interactions, leading to improved catalytic activity and enantioselectivity in HKR compared with its homogeneous analogues, especially at low catalyst/substrate ratios.

Our Schiff has come in: A homochiral porous lamellar solid based on chiral unsymmetrical Schiff base metal complexes was assembled by using coordination and hydrogen bonds (see picture). The host features a flexible helical framework and chiral amphiphilic channel surfaces capable of multiple interactions with guest species.A homochiral lamellar supramolecular host system has been developed by treating 3-[(E)-{[(1R,2R)-2-aminocyclohexyl]imino}methyl]-4-hydroxybenzoic acid (H(2)L) with copper nitrate and characterized by a variety of techniques including microanalysis, IR spectroscopy, thermogravimetric analysis (TGA), circular dichroism (CD) spectroscopy, and powder and single-crystal X-ray diffraction. Tridentate Schiff base L ligands link adjacent metal centers to form 1D coordination polymeric chains using tridentate N(2)O donors and carboxylate groups, while interchain metal-oxygen and hydrogen-bonding interactions further link 1D polymeric chains to a porous lamellar solid. The host features a flexible helical framework for guest inclusions and chiral amphiphilic channel surfaces lined with amine hydrogen atoms and aliphatic groups capable of multiple interactions with guest species. It allows for the development of an efficient approach for highly enantioselective separation of racemic secondary alcohols by inclusion crystallization followed by distillation (>99.5 % ee). In addition, the host including different alcohols exhibits guest-responsive ferroelectric behavior.

Three homochiral 3D frameworks are assembled based on periodically ordered arrays of helices built from axial chiral 3,3'-bipyridine-5,5',6,6'-tetramethyl-2,2'-dimethoxy-1,1'-biphenyl ligands and linearly coordinated Ag(I) ions. The aggregation behavior of silver salts and the ditopic ligand in solutions was investigated by a variety of techniques, including (1)H NMR, UV-vis, CD, GPC and MALDI-TOF. The cationic polymer skeleton exhibits an unprecedented conformational polymorphism in the solid-state, folding into two-, three- and four-fold helices with NO(3)(-), PF(6)(-) and ClO(4)(-) as the counteranion, respectively. The two-fold helices cross-link via argentophilic Ag-Ag interactions to form sextuple helices, which lead to a three-dimensional (3D) chiral framework. The three-fold or four-fold helices, on the other hand, self-associates in pairs to form three-dimensional tubular architectures. This anion-dependent self-assembly behavior can be rationalized by considering the sizes, geometries and binding abilities of the counteranions and subsequent chain conformation to minimize steric repulsions and maximize secondary interactions.

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Three 3D Ag-based metal-organoboron frameworks with unprecedented multiple topological isomerism of 3-connected networks were assembled and could control the release of silver ions in biocidal concentration in solution giving excellent antibacterial activities and durability against gram-negative bacteria and gram-positive human pathogens.

5), were assembled by using a novel 8-hydroxyquinolinate derivative H 2 L with different metal ions. Complex 1 features a 3D porous network consisting of meso-helical chains (P + M) built from metal−ligand coordination bonds. The adjacent dinuclear Zn II building blocks in 2 are connected together to generate a 2D grid network. In complex 3, each binuclear motif is bound to four Zn II ions to produce a 2D layer structure that stacks into a 3D porous structure. The framework of complex 4 is isostructural to 5, featuring a 2 1 helical chain built from [M 2 L 2 ] units (M = Mn or Co). The adjacent meso-helices associated in parallel are interconnected by the phenolate μ 2 -O atoms of H 2 L to give rise to a 2D network. Distinct solid-state luminescence properties of 1−3 were observed, arising from their different metal nodes and frameworks. In particular, complex 1 exhibited excellent stability in both common organic solvents and H 2 O, thus facilitating its utility as a chemical sensor. Remarkably, luminescent 1 showed highly sensitive detection for nitroaromatic molecules in methanol and Fe 3+ ion in H 2 O even in the presence of other interfering metal cations.

A Co-based complex displayed the highest photocatalytic performance for CO2 to CO conversion in aqueous media.

A homochiral 3D porous metal-organic framework was assembled from a chiral dicarboxylic acid-functionalized Cu(salen)-based catalyst and could serve as an efficient heterogeneous catalyst for aziridination and allylic amination of olefins. Besides easy separation and reuse of the catalyst, the chiral framework confinement could impart substrate size selectivity, enhance catalyst activity, and induce product enantioselectivity.