Versatile coordination of N-(diisopropoxyphosphoryl)-p-bromothiobenzamide towards Zn(II) and Cd(II)

Reaction of the potassium salt of N-(diisopropoxyphosphoryl)-p-bromothiobenzamide p-BrC6H4C(S) NHP(O)(OiPr)(2) (HL) with Zn(II) and Cd(II) cations in aqueous EtOH leads to the three different complexes: [Zn(L-O,S)(2)] (1), [Cd(p-BrC6H4C(S)NH2-S)(L-O,S)(2)] (2) and [Cd(HL-O)(2)(L-O,S)(2)] (3). The structures of these compounds were investigated by single crystal X-ray diffraction analysis, IR, H-1 and P-31 NMR spectroscopy, MALDI TOF spectrometry, and microanalysis. The Zn(II) atom in complex 1 is in a distorted tetrahedral O2S2 environment formed by the C=S sulfur atoms and the P=O oxygen atoms of two deprotonated ligands. Complex 2 has a trigonal-bipyramidal coordination core, Cd(O-ax)(2)(S-eq)(3), and two deprotonated ligand molecules L are coordinated in the axial positions through the oxygen atoms of the P=O groups. The trigonal plane is formed by the sulfur atoms of two anionic ligands and one p-bromothiobenzamide. The Cd(II) cation in complex 3 has an octahedral environment, (O-ax)(2)(O-eq)(2)(S-eq)(2), with two neutral ligand molecules coordinated in the axial positions through the oxygen atoms of the P=O groups. The equatorial plane is formed by two anionic ligands in a typical 1,5-O,S-coordination mode. The corresponding neutral and deprotonated ligands are in a trans disposition. (C) 2009 Elsevier Ltd. All rights reserved.