Synthewes, Structures And Properiy Studies Of Coordination Polymer Materias Assembled From Modified Aromatic Benzoic Acid

Supramolecular coordination polymer have been the research focus of the coordinationchemistry and crystal engineering because for their novel attractive structure, which more fortheir extremely broad applications such as magnetic, gas adsorption, catalysis, nonlinearoptics, biology, etc. Among the coordination polymers, the reaction of aromatic carboxylicacid ligands with metal is an important key in the coordination chemistry. Carboxylic acidligands have a strong bridged ability and varity coordination models. Specily, aromaticcarboxylic acid exist a large Ï€ electrons system for electron transfer, these are excellentconditions for the synthesis of aromatic carboxylic acids coordination polymers. In this paper,we have successfully prepared four complexes by employing three modified aromatic benzoicacids:2-（4-isopropylbenzene formyl） benzoic acid,2-（4-ethylbenzene formyl） benzoic acid,2-（4-methylobenzene formyl） benzoic acid and different auxiliary co-ligands with Zn^II,Cr^II,Cu^IItransition metal ions under hydrothermal conditions. We characterized by IR,elemental analyses and X-ray single crystal diffractions. The thermal stabilities andluminescence properties of these complexes have also been studied.1. We have prepared two new Zn^II, Cr^IIcomplexes by2-（4-isopropyl benzene formyl）benzoic acid and the N-donor auxiliary co-ligands4,4’-bpy，2,2’-bpy under the samehydrothermal condition.Zn2（L¹ï¼‰₃（4,4’-bpy）（OH）（1）[Cd （L¹ï¼‰₂（2,2’-bpy） H₂O]·2H₂O （2）Complex1crystallizes in P2（1）/n space, which possess one-dimensional chaincoordination frameworks. The crystal is mainly stabilized by strong intermolecular hydrogenbonds. The1D chain further connect with each other to form a hydrogen bond channel（2Zn-4O）. The supramolecular framework construct by classic O-H···O hydrogen bonds. andπ···π stacking interactions between the pyrimidine rings. Structure analysis reveals thatcomplex2crystallizes in P21/c space. The most striking feature of2is the existence of adiscrete water cluster. The water clusters also have strong hydrogen bonding with the O fromL^1-, to form a regular1D chain. The two1D chains are connected by C-H···O interactionswith a distance of c-direction to form a regular2D plane.The water clusters play an importantrole in the stability of the structure. The luminescence properties and the thermal stabilities for1-2have been investigated.2. We have synthesized one new complex by the reaction of Cr^II,2-（4-ethylbenzeneformyl） benzoic acid and1,10-phen under hydrothermal conditions. Cd （L²ï¼‰₂（1,10-phen）（3）Complex3crystallizes in Pccn which is0D structures. The non-covalent interactions（O–H···O, C–H···O, interactions） extend compound3into3D supramolecular networks. Theluminescence properties and the thermal stabilities for3have been investigated.3. We have synthesized one new complex by the reaction of CuII,2-（4-methylobenzeneformyl） benzoic acid and2,2-bpy under hydrothermal conditions.Cu₂（L³ï¼‰₄（2,2’-bpy）₂（4）Complex4crystallizes in P-1which is0D structures. Compound4exhibits1Dwavelike chains though π···π interactions. compound4build into2D supramolecularnetworks by O–H···O, C–H···O interactions The thermal stabilities for4have beeninvestigated.