Dirhenium(III,III) trithiocarbamato complexes: experimental and theoretical investigation

The green colored trithiocarbamato complexes of dirhenium(III,III) of type [Re2(μ-η2-SLR)2(η2-LR)3][ReO4] (4(LR)), where LR represents the dithiocarbamato ligands [LR = S2CNEt2, 4(LEt) and S2CN(CH2)4, 4(LPyr)], have been synthesized in moderate yield by reacting Re2(μ-O2CCH3)4Cl2 (1) and sodium salt of diethyldithiocarbamate or pyrrolidinedithiocarbamate in boiling ethanol under nitrogen atmosphere. The spectral (IR, UV–vis, NMR) and electrochemical properties of the complexes are reported. The identity of complex 4(LEt) has been established by single-crystal X-ray structure determination. The density functional theory (DFT) calculations rationalized the electronic structure of complexes 4(LR) in comparison with dithiocarbamato complexes of dirhenium(II,II) and dirhenium(III,II). The absorption spectra of the 4(LR) complexes are scrutinized by the time-dependent DFT analysis.