Coordination compounds of cobalt, nickel, copper, and zinc with 2-bromo-3-phenylpropenal benzoylhydrazone and thiosemicarbazone

By X-ray structural analysis the crystal structure of 2-bromo-3-phenylpropenal benzoylhydrazone (HL) was determined. The molecule is not flat. In the crystal the HL molecules form infinite chains with reciprocal van der Waals interaction. 2-Bromo-3-phenylpropenal hydrazone (HL) and thiosemicarbazone (HL′) react with cobalt, nickel, copper and zinc chlorides, nitrates and acetates to form coordination compounds of the composition Cu(HL)(L) 2 [HL = C 6 H 5 -CH=CBr-CH=N-NH-C(O)-C 6 H 5 ], MX 2 ·2 HL′· n H 2 O [M = Co, Ni, Cu, Zn; X = Cl, NO 3 , HL′ = C 6 H 5 -CH=CBr-CH=N-NH-C(S)-NH 2 ; n = 0–3], MX 2 ·HL· n H 2 O [M = Ni, Cu; n = 0, 1], and ML′ 2 · n H 2 O [M = Co, Ni, Zn; n = 0–3]. The same reactions in the presence of amines (A = C 5 H 5 N, 2-CH 3 C 5 H 4 N, 3-CH 3 C 5 H 4 N, 4-CH 3 C 5 H 4 N) afford complexes of the composition CuALCl and MALX· n H 2 O [M = Cu, Ni; X = Cl, NO 3 ; n = 0–2]. Structure of the coordination node in the amine-containing copper derivatives is polynuclear, in complexes Cu(HL)(L) 2 is octahedral, in other compounds it is tetrahedral. The azomethines (HL and HL′) in these complexes behave as bidentate N,O and N,S ligands. Thermolysis of the complexes includes a step of dehydration (60–90°C) and complete thermal decomposition (430–590°C).