Formation of cyclo- and polystannanes by dehydrogenative stannane coupling catalyzed by platinum(II) complexes

Reaction of (PhMe2P)2PtMe2 or [(κ2-P,N)-Ph2PC2H4NMe2]PtMe2 with an excess of H2SnBu2 or H2SnPh2 resulted in the catalytic formation of cyclo-, oligo- and/or polystannanes. In the reaction of (PhMe2P)2PtMe2 with H2SnBu2, linear oligomeric species H(SnBu2)nH were observed in the initial stage of the reaction, which eventually converted into cyclostannanes. Only polystannanes were observed in the reaction of [(κ2-P,N)-Ph2PC2H4NMe2]PtMe2 with H2SnBu2. The reactions of H2SnPh2 were similar, but more difficult to analyze due to redistribution reactions and the formation of insoluble products. The mechanism of the reactions is clearly different to that previously observed for HSnR3 because metal complexes indicative of oxidative addition/reductive elimination reactions were only observed as minor products.