Structural studies on zinc(II) complexes with 2-benzoylpyridine-derived hydrazones

2-Benzoylpyridine-phenylhydrazone (H2BzPh), 2-benzoylpyridine-para-chloro-phenylhydrazone (H2BzpClPh), and 2-benzoylpyridine-para-nitro-phenyl (H2BzpNO2Ph) hydrazone were obtained and fully characterized, as well as their zinc(II) complexes [Zn(H2BzPh)Cl2] (1), [Zn(H2BzClPh)Cl2] (2) and [Zn(H2BzpNO2Ph)Cl2] (3). During the syntheses of complex 1 a second product crystallized, which was characterized as [Zn(2BzPh)2] (1a). Upon re-crystallization in 1:9 DMSO:acetone conversion of 2 into [Zn(H2BzpClPh)Cl2] · H2O (2a) and of 3 into [Zn(2BzpNO2Ph)Cl(DMSO)] (3a) occurred. The crystal structures of 1a, 2a and 3a were determined. In 1a the two nearly perpendicular H2BzPh ligands give rise to a distorted octahedral environment around the metal. The 5-fold coordination around the metal is completed with two chloride ions in 2a and with one chloride and one oxygen atom from DMSO in 3a.