Synthesis and spectral studies on nitrogen donor adducts of bis(4-ethylpiperazinecarbodithioato-S,S′)M(II) (M = Zn, Cd) and use of adducts of cadmium dithiocarbamate for the preparation of cadmium sulfide

Abstract

[M(4-epzdtc)₂(py)], [M(4-epzdtc)₂(1,10-phen)], and [M(4-epzdtc)₂(2,2′-bipy)] (where M = Zn(II), Cd(II); 4-epzdtc⁻= 4-ethylpiperazinecarbodithioate) were synthesized and characterized by IR and NMR (¹H, ¹³C, HSQC and HMBC) spectra. A single-crystal X-ray analysis was carried out for [Zn(4-epzdtc)₂(py)]. The N¹³CS₂ chemical shifts of [M(4-epzdtc)₂] and its adducts follow the order: [M(4-epzdtc)₂] (ca 202 ppm) < [M(4-epzdtc)₂(py)] (ca 204 ppm) < [M(4-epzdtc)₂(N,N)] (N,N = 1,10-phen, 2,2′-bipy) (ca 206 ppm), due to the change in coordination number. Single-crystal X-ray structural analysis of [Zn(4-epzdtc)₂(py)] showed that zinc is five-coordinate with four sulfurs from dithiocarbamate and one nitrogen from pyridine. This complex adopts a geometry intermediate between the tetragonal pyramid (C_4v) and trigonal bipyramid (D_3h). [Cd(4-epzdtc)₂] and its adducts were used as single source precursors for preparation of CdS. The as-prepared CdS was characterized by powder X-ray diffraction, UV-Vis absorption, and fluorescence spectroscopy. The UV-Vis absorption spectra of CdS particles indicate a blue shift in the absorption spectra due to the quantum size effect.

Keywords:

• 4-Ethylpiperazinecarbodithioate
• Sulfide
• Cd(II)
• Crystal structure

Acknowledgments

We are grateful to SAIF, Indian Institute of Technology Madras for recording NMR spectra of all compounds.