Radical anions of 1,1-azoliumdithiocarboxylates

Abstract

The 1,1-azoliumdithiocarboxylate cAAC^Me-CS₂ (1a) was prepared and its redox chemistry was evaluated and compared to NHC based dithiocarboxylates IDipp-CS₂ (1b) and IMes-CS₂ (1c). Radical anions [carbene-CS₂]˙⁻ were prepared by metallic reduction as the potassium or magnesium ion complexes [K(18-crown-6)(cAAC^Me-CS₂)] (2a), [K(18-crown-6)(NHC-CS₂)] (NHC = IDipp: 2b, IMes: 2c), and [Mg(^DippNacNac)(cAAC^Me-CS₂)] (3) and extensively characterized (SC-XRD, EPR, UV/VIS/NIR, DFT). These complexes represent the first examples of isolated radical anions of 1,1-dithiolenes.