Structure of hypercoordinated monoorganodihalostannanes in solutions and in the solid state: the halogen effect

The hypercoordinated monoorganodibromides were synthesized by interaction of tribromides RSnBr3 with O-TMS derivatives of N,N-disubstituted amides. In solution behavior of bromides differs from the analogous chlorides, including equilibrium dimer/monomer adducts with DMSO. In the case of chlorides the equilibrium is shifted toward monomers. In solid state tin compounds are dimeric.