Structural assemblies of four Cd(II) coordination polymers based on 5-methylisophthalic acid

Four new metal-organic coordination polymers, Cd(mip)(DMF)(1), Cd(mip)(EtOH)(2), Cd-2(miP)(2)(H2O)(5)center dot 3H(2)O (3), Cd(miP)(bPP)(H2O)center dot H2O (4) (H(2)mip = 5-methylisophthalic acid, bpp = 1,3-di(4-pyridyl)propane) have been hydro(solvo)thermally synthesized and characterized by IR, thermogravimetric (TG) analysis, powder X-ray diffraction and single-crystal X-ray diffraction. 1 and 2 are isostructural, and two adjacent Cd centers are bridged by four carboxylate groups in mu(2)-carboxylato-kappa O-1:kappa O-1' and mu O-2; kappa O-2,O' fashion to form a linear (Cd-O-Cd)(n) chain. The adjacent (Cd-O-Cd)(n) chains are further connected by mip bridges to form a 3D framework. 3 features two types of chiral layers: One left-handed and another right-handed, which lead to racemic solid-state compound. 4 exhibits a twodimensional wave-like (2D) (4,4) layer structure with infinite 1D linear chain. In addition, the luminescent properties of 1-4 are also discussed. Crown Copyright (C) 2011 Published by Elsevier Masson SAS. All rights reserved.