Preparations, sulphinate coordination, and thermal decomposition of some bismuth triarenesulphinates

Bismuth triarenesulphinates, Bi(O₂SR)₃ [R = Ph, p-MeC₆H₄, p-ClC₆H₄, 2, 4, 6-(Me₂CH)₃C₆H₂, and p-MeCONHC₆H₄], have been prepared by reaction of bismuth triacetate with the appropriate arenesulphinic acids in glacial acetic acid, and the first two compounds have also been obtained by reaction of triphenyl-bismuth with the appropriate mercuric arenesulphinates. The sulphur-oxygen stretching frequencies of the bismuth sulphinates are indicative of O-sulphinate coordination, and the compounds are considered to be polymeric with bridging O-sulphinate groups and six-coordinate bismuth. Thermal decomposition of Bi(O₂SR)₃ (R = Ph, p-MeC₆H₄, or p-ClC₆H₄) under vacuum gave the corresponding triarylbismuth compounds and sulphur dioxide, the preparation of tri-p-chlorophenylbismuth being accompanied by formation of di-p-chlorophenyl sulphone and S-p-chlorophenyl p-chlorobenzenethiosulphonate. Pyrolysis of the other triarenesulphinates did not yield organobismuth compounds.