Flexibly Coordinating Tris(arylamido)stannates as Ligands: A [Rh]+/[Sn]- Zwitterion as an Intermediate in the Formation of Rh−Sn Complexes

Reaction of the lithium stannate MeSi{SiMe 2 N(3,5-xyl)} 3 SnLi(OEt 2 ) ( 1 ) with 1 / 2 molar equiv of [RhCl(COD)] 2 gave the zwitterionic heterodinuclear complex [MeSi{SiMe 2 N(3,5-xyl)} 2 Sn{SiMe 2 N(η 6 -3,5-xyl)}Rh(COD)] ( 2 ), in which one of the peripheral N-bonded 3,5-xylyl groups acts as an η 6 -aryl ligand to which the {Rh(COD)} + cation is bonded. Reaction of the 18-electron complex 2 with nucleophiles leads to an attack at the late transition element, which moves over to the tin atom to form the Rh−Sn-bonded 16-electron complexes [MeSi{SiMe 2 N(3,5-xyl)} 3 SnRh(L)(COD)] (L = Ph 3 P ( 3 ), (PhO) 3 P ( 4 ), CyNC ( 5 )).