Synthesis and structural characterization of metal complexes of 2-formylpyrrole N-4-methylthiosemicarbazone (4ML(1)) and 2-acetylpyrrole N-4-methylthiosemicarbazone (4ML(2)). The X-ray crystal structures of [Ni(4ML(1)-H)(2)], [Pd(4ML(1)-H)(2)] and [Cd(4ML(2))(2)I-2]

Reaction of N-4-methyl-2-[1-(pyrrol-2-yl)methylidene] hydrazine carbothioam ide (4ML(1)) and N-4-methyl-2-[1-(pyrrol-2-yl)-ethylidene] hydrazine carbot hioamide (4ML1) with zinc(II), cadmium(II) and mercury(II) halides afforded complexes with formulas [M(L)X-2] [(L; M; X) = (4ML(1); Cd; Cl) (4), (4ML( 1); Hg; Cl, Br, I) (7-9), (4ML(2); Cd; Cl) (17), (4ML(2); Hg; Cl, Br, I) (2 0-22)] or [M(L)(2)X-2] [(L; M; X)= (4ML(1); Zn; Cl, Br, I) (1-3), (4ML(1); Cd; Br, I) (5, 6), (4ML(2); Zn; Cl, Br, I) (14-16), (4ML(2); Cd; Br, I) (18 , 19)]. Reaction of 4ML(1) with salts of copper(II), nickel(II), palladium( II) and platinum(II) afforded complexes of formula [M(4ML(1)-H)(2)] (10-13) . Crystals of 11, 12 and 19 were studied by X-ray diffractometry, and all n ew compounds were characterized by elemental analysis, mass spectrometry, a nd IR, electronic and H-1 and C-13 NMR spectroscopy and, when pertinent and allowed by the solubility of the compound, Cd-113 or Hg-199 NMR spectrosco py. In the complexes of Group 12 metals, both ligands are neutral and S-mon odentate. In the complexes of copper or Group 10 metals, 4ML(1) is monodepr otonated and S,N-bidentate.