REDUCTION OF CARBENE ADDUCTS OF CARBON-DISULFIDE - NOVEL ACCESS TO 1,1-DITHIOLATES

The carbene adducts 5a,b react with two equivalents of potassium to fo rm the I,l-dithiolate salts 6a,b which are converted into the olefins 7a,b on treatment with iodomethane. On further reaction with excess io domethane the imidazolium salts 8a,b are obtained. 7b reacts with iodi ne to form the cationic dithiocarboxylic ester 9b. Electrochemical red uction of 5b las investigated by cyclic voltammetry and chronocoulomet ry) proceeds through a stepwise ECEC reaction mechanism to a dianion w hich undergoes a follow-up reaction. The rather negative values of red ox potentials (E-1(0) = -2.51 V, E-2(0) = -2.43 V vs, ferrocene) confi rm the influence of the ir-electron distribution.