Base-induced reversible H2 addition to a single Sn(ii) centre

Abstract

A range of amines catalyse the oxidative addition (OA) of H₂ to [(Me₃Si)₂CH]₂Sn (1), forming [(Me₃Si)₂CH]₂SnH₂ (2). Experimental and computational studies point to ‘frustrated Lewis pair’ mechanisms in which 1 acts as a Lewis acid and involve unusual late transition states; this is supported by the observation of a kinetic isotope effect for Et₃N. When DBU is used the energetics of H₂ activation are altered, allowing an equilibrium between 1, 2 and adduct [1·DBU] to be established, thus demonstrating reversible oxidative addition/reductive elimination (RE) of H₂ at a single main group centre.