METAL-COMPLEXES WITH GUANIDINE DERIVATIVE S AS LIGANDS - CRYSTAL-STRUCTURES OF [ZN(CNGE)(2)(SCN)(2)]CENTER-DOT-2H(2)O AND ZN(EOGE)BR-2 (CNGE EQUALS CYANOGUANIDINE - EOGE EQUALS 1-ETHOXYIMINOMETHYLGUANIDINE)

Crystals of [Zn(cnge)(2)(SCN)(2)]. 2H(2)O (1) were obtained by evapora tion of an aqueous solution of Zn(SO4). 7H(2)O, KSCN, and cyanoguanidi ne. Crystals of Zn(eoge)Br-2 (2) were obtained by reaction of ZnBr2 an d cyanoguanidine in ethanol/water. Both compounds are monoclinic, spac e group C2/c, 1: Z = 4, a = 1919.6(7), b = 467.3(2), c = 18385(6)pm, b eta = 112.99(3)degrees, 2: Z = 8, a = 1799.5(6), b = 878.7(2), c = 136 7.2(5) pm, beta = 101.52(3)degrees. In 1 each Zn is bonded to two cyan oguanidine molecules and via the N atoms to two NCS groups. Intermolec ular hydrogen bonds lead to chains along the a-axis, and these chains are again connected via hydrogen bonds to the two crystal water molecu les. In the course of the formation of 2, the cyanoguanidine reacted w ith the ethanol to form 1-ethoxyiminomethylguanidine. This ligand form s chelate rings with the Zn atoms, which are tetrahedrally coordinated by the two imino N atoms of the ligand and by two bromine atoms.