The synthesis and reaction of heterocyclic thiophosphoryl chlorides with AlCl3 or CF3SO3Ag. An attempt to obtain lambda(5)sigma(3)-thiophosphoryl cations

Two new heterocyclic thiophosphoryl chlorides (2), derivatives of 1,3,2-ben zodiazaphosphole, are synthesized. The reaction of respective thiophospbory l chlorides (1) and (2) with AlCl3 affords dimeric heterocyclic diphosphoni um dications 3 and 4. The reaction of 2a with CF3SO3Ag gives rise to dimeri c anhydride 5 instead of the expected lambda(5)sigma(3)-thiophosphoryl cati ons. The results show that lambda(5)sigma(3)-thiophosphonium cations incorp orated into a thiadiaza-phospholic system (1) or benzodiazaphospholic syste m (2) are not stable, and undergo a structural rearrangement to give a lamb da(4)sigma(4)-phosphorus-centre products.