Some Unusual Properties of Tris(2,6-dimethoxyphenyl)phosphine Sulfide and the Related Compounds

Abstract

Abstract The title sulfide {2,6-(MeO)2C6H3}3P=S [abbr. (2,6)3P=S] reacted with acids to form a novel mercaptophosphonium salt [(2,6)3P–SH]X, solution thermolysis of which in the absence or presence of triphenylphosphine resulted in the unusual desulfurization to give the tertiary phosphonium salts [(2,6)3P–OH]X. (2,6)3P=S also reacted with alkyl iodides or bromides under mild conditions to give stable (alkylthio)phosphonium salts [(2,6)3P–SR]X (R=Me, Et, n-Bu), which reacted with thiols at room temperature in the presence of a catalytic amount of the tertiary phosphine (2,6)3P to give [(2,6)3P–H]X and unsymmetrical disulfides.