The reactions of triethylamine-activated octasulfur with thioarsinites, L2As-SPh (L = Me, Ph), Bunsen's cacodyl disulfide, Me2As(S)-S-AsMe2, and triphenylarsine

摘要

The reactions of L2As-SPh (L = Me or Ph) with varying amounts of octasulfur, activated by triethylamine, aiming at the preparation of L2As-S-AsL2 and L2As(S)-S-AsL2 were slow and very complex in the sense that the composition in solution changed on work up. Generally, the disulfide L2As(S)-S-AsL2 was formed admixed with L2As-S-NEt3+ and L2As-S-. The disulfide Ph2As(S)-S-AsPh2 was not stable during chromatography giving sulfur (S-8) and Ph2As-S-AsPh2 which was autoxidized to Ph2AsO2H center dot Ph2As(S)OH. Bunsen's cacodyl disulfide, Me2As(S)-S-AsMe2, was electrophilic toward activated octasulfur reacting at As=S sulfur. Triphenylarsine was oxidized to pure triphenylarsine sulfide in boiling ethanol by octasulfur in the presence of a catalytic amount of triethylamine in short time and with excellent yields.