Base-catalysed disproportionation and addition reactions of hexaalkylditins

Abstract

Under polar conditions asymmetric hexaalkylditins, R3SnSnR′3, disproportionate rapidly at room temperature to give the symmetrical ditins R6Sn2 and R′6Sn2. The equilibrium constants observed for a series of such reactions (R = Me; R′ = Et, Pt, Bu, i-Bu) point to a predominance of steric rather than inductive effects. Hexaalkyl-ditins (and -digermanes) also react readily under polar conditions with carbon---carbon triple bond systems as well as with diethyl azodicarboxylate