Anirban Karmakar

Reaction of 3-aminobenzenesulfonic acid (HL1) with Cu(NO3)2·2.5H2O in H2O/DMF leads to the formation of the new bis(3-aminobenzenesulfonato-κN)-diaqua-bis(dimethylformamide-κO)-copper(II) complex [Cu(L1)2(DMF)2(H2O)2] (1) (HL1 = 3-aminobenzenesulfonic acid and DMF = N,N-dimethylformamide). Single crystal X-ray analysis reveals that the hexacoordinated copper(II) center adopts a distorted octahedral geometry with trans-oriented two 3-aminobenzenesulfonate ligands (L1−), two water and two dimethylformamide (DMF) molecules. Comparison of its crystal structure with that of the known bis(4-aminobenzenesulfonato-κN)diaquabis(dimethylformamide-κO)-copper(II) complex [Cu(L2)2(DMF)2(H2O)2] (2) (HL2 = 4-aminobenzenesulfonic acid) discloses that 1 and 2 are the isomers with an identical empirical formula (C18H30CuN4O10S2) and equal numbers of same coordinated solvents (DMF and water). H-bonded supramolecular structures and their corresponding topological analyses revealed a 2D with 6-connected hxl/Shubnikov plane net (3,6) for 1 and a 3D with 8-connected bcu; 8/4/c1; sqc3 net for 2, which are completely different.