Two d10-metal-organic frameworks based on polydentate Schiff-base ligand derived from biphenyl dihydrazide: Synthesis, crystal structure and luminescent properties

Two two-dimensional d(10)-metal-organic frameworks {[CdL2(NO3)(2)]center dot(H2O)(6)}(n) (1) and {[Zn2L4(NCS)(4)]center dot(H2P)(4)center dot(CH3OH)}(n) (2) have been synthesized and characterized by IR, elemental analyses, XRPD, TG technique and complete X-ray single crystal structure analyses, where L is bis(pyridin-3-ylmethylene)bipheny1-2,2'-dicarbohydrazide. The two polymers display similar 2D layer network containing tetranuclear metallacyclic ring units [(M4L4)-L-II] (M = Cd (1) and Zn (2)) in the chair conformation, in which each ligand L acts as a bidentate bridging ligand to bind two metal centers through two terminal pyridyl N-donors. The solvent molecules were filled into the macrometallacyclic ring units through multiform hydrogen bonds. In addition, the C-H center dot center dot center dot pi interactions are found in the 2D networks and also play an important role in stabilizing the networks. The luminescent properties of 1 and 2 were investigated in the solid state at room temperature. (C) 2012 Elsevier B.V. All rights reserved.