Tin–magnesium transmetallation reactions

Sulfur-functionalized methyltin compounds nBu3SnCH2S(O)iR (i=0, 1, 2; R=Me, Ph) underwent transmetallation with Grignard compounds MgR′X (R′=Me, nBu, Ph; X=Cl, Br, I) and diorganomagnesium compounds MgR′R″ (R′/R″=Me/Me, nBu–sBu) to provide Sn(nBu)3R and Mg[CH2S(O)iR]X and Mg[CH2S(O)iR]R″, respectively. Analogously, the reaction of nBu3SnCH2P(O)Ph2 with Mg(nBu)Br afforded quantitatively Mg[CH2P(O)Ph2]Br and Sn(nBu)4. Transmetallations between nBu3SnCH2YMe2 (Y=N, P) and MgMe2 proceeded only in the presence of catalytic amounts (10–20 mol%) of LinBu yielding Mg(CH2YMe2)Me and Sn(nBu)3Me/Sn(nBu)4.