Synthesis and characterization of cadmium and zinc dithiocarbamate complexes derived from α-aminoacid L-proline

Abstract

Dithocarbamate metal complexes have been used to prepare nanoparticles and nanowires of a variety of semiconducting metals including CdS, ZnS, PbS, and EuS. The two new cadmium (II) L-Proline Dithiocarbamate and zinc (II) L-proline dithiocarbamate complexes have been synthesized. Both of the metal complexes are able to produce semiconductor sulphides, nanoparticles which are applicable in the electronic industries. The amino acid L-proline has the unique property, it is the only DNA determined amino acid which has a secondary five membered cyclic amino group alpha to the carbonyl group in the biosystem. Metal dithiocarbamate which is derived from L-proline is able to produce the corresponding metal sulphides as nanoparticles and nanowire. This is very much applicable in Thin Film Technology. Besides, the Zinc complex is used as a drug in increasing the immune system of the body against bacteria and viruses. Zinc dithiocarbamate derived from alpha aminoacid is biocompatible so that it can be used as pharmaceutical products. The two complexes exhibit the important NCS2 peak from 202.73-215 in 13C NMR, attributing to the presence of the dithiocarbamate ligand. A resonance signal around δ 4.92 is due to COOH-proton in 1H NMR. The complexes also shows the important IR frequencies, ν(CN), ν(CS) and ν(CO) in the ranges 1443-1430 cm-1, 954-945 cm-1 , and 1720-1712 cm-1 , respectively. LMCT transitions have been observed at λ 214 nm for the Cd complex. Based on the thermo gram the complexes are stable up to 200°C, and fast decomposed to produce M(SCN)2 at 400C and finally MS(M= Cd), as residue at 600°C by slow steps. From FTIR, 1H, 13C NMR, only dithiocarbamate sulphurs are coordinated to metal and not the carboxylate oxygen in the two complexes.