Several chiral copper(II) complexes of optically active Schiff bases (R,R)-4a-c, which have central seven-membered chelate rings, have been synthesized and characterized. X-ray single crystal analysis of a typical compound indicated that the complex is monomeric and the geometry around the metal atom is very distorted tetrahedral. All the complexes have been tested as catalysts for asymmetric oxidation of methyl phenyl sulfide. The mechanism of the catalytic reaction in the presence of these complexes has been tentatively elucidated.

A chiral heptanuclear nickel(II) complex [NiII(NiII 2L)3(μ3-OH)2]·3H2O [H4L=(2R,3R)-1,4-bis(3,5-di-tert-butylsalicylideneamino)-2,3-butanediol], containing two μ3-OH bridges, has been prepared and structurally characterized; its thermal and magnetic properties were investigated.

Two macrocyclic dinuclear zinc(II) complexes (1a and 1b) have been self-assembled in the presence of pyridine and 2,2 -bipyridine, respectively, to form μ2-OH-bridged bimacrocycles with a Zn4O4 cavity through coordination bonding. The X-ray structural analysis reveals that both compounds {2a: [Zn4La 2(OH)2]2(ClO4)2; 2b: [Zn4Lb 2(OH)2]2(ClO4)2} have an open-mouthed sandwich-like structure with π−π interactions between parts of two phenyl rings to strengthen two hydroxyl groups connecting the metal atoms in the same direction of the macrocycle. Furthermore, nonclassical C−H•••Cl intermolecular interactions have been observed in the crystal of 2b. In addition, the reaction of 1a with quinoline derivatives has yielded novel hydrogen-bond-supported donor-acceptor complexes {3a: [Zn2 La(H2O)2(C10H9N)2](ClO4)2}. The crystallographic study of the complex containing 2-methylquinoline indicates that two 2-methylquinoline molecules are linked to two coordinating water molecules above and below the macrocyclic framework through O−H•••N hydrogen bonds. The 2-methylquinoline plane interacts in a face-to-face fashion with the phenyl ring of adjacent macrocyclic frameworks, forming an ordered arrangement where one macrocycle and two 2-methylquinolines are arrayed alternately with almost the same separation. The interplanar distance mentioned before is ca. 3.6Å.

Two coordination polymers (2a and 2b) containing dinuclear zinc(II) macrocyclic components have been unexpectedly obtained when pyrazine and 2-methylpyrazine were used to react with dinuclear zinc(II) macrocyclic complexes 1a and 1b, respectively. The X-ray crystal structural study indicated that the coordination environment around each Zn(II) atom in 2 is a five-coordinated distorted pyramid in which the apical position is occupied by a bridging formate anion, unlocalized, in an end to end fashion. The formate group acts as a bidentate bridging ligand to link two adjacent macrocyclic units forming a chain polymer. In addition, Hbonding interactions are observed in the crystal packing of 2a and 2b, which could be described as two-dimensional networks.

The self-assembly assisted by 2,20-bipyridine (2,20-bpy) protected zinc(II) species with 1,2-benzenedicarboxylate (1,2-BDC) has yielded a novel one-dimensional single helical coordination polymer of