Alkylthiolation of ambident anions derived from some unsaturated organic sulfides

Abstract

AbstractReaction of the anions derived from 1,1‐bis(alkylthio)‐2‐alkynes RCCCH(SC2H5)2 (R = alkyl, vinyl or phenyl) with dialkyl disulfides R′SSR′ or alkyl alkanethiosulfonates R′SSO2R′ gives 1,1,3‐tris(alkylthio)‐1,2‐alkadienes RC(SR′) = C = C(SC2H5)2 in good yields. Alkylthiolation of CH3SC ≡ CC(SC2H5)2 with CH3SSCH3 affords (CH3S)2C = C = C(SC2H5)2. The 1‐alkynyl sulfides C2H5C≡CSC2H5 and CH3C≡CSCH3 have been converted into CH3C(SC2H5)=C=C(SC2H5)2 and (CH3S)2C = C=C(SCH3)2, respectively by reaction with alkali metal amide in liquid ammonia and dialkyl disulfide. The latter compound dimerises on heating. Tris(alkylthio)allenes R″CH2C(SR′)=C=C(SC2H5)2 isomerise to the conjugated dienes R″CH=C(SR′)‐CH=C(SC2H5)2 when heated in the presence of acids. Ethylthiolation of the anions of R′CH2C(R″)=C(SC2H5)2 (R″ = H or CH3; R′ = H, CH3 or SC2H5) gives predominantly R′CH=C(R″)‐C(SC2H5)3 as isolable products.