The 1H, 13C, 15N and 117Sn NMR study of the intramolecular Sn-N interaction in tri- and tetraorganotin compounds containing the chiral 2-(4-isopropyl-2-oxazolinyl)-5-phenyl ligand

A series of novel tri- and tetraorganotin compounds containing the optically active 2-(4-isopropyl-2-oxazolinyl)-5-phenyl ligand has been synthesized. All the novel compounds have been characterized, especially by means of the multinuclear NMR investigation, the results of which are discussed. A number of arguments based on the 13C, 15N and 117Sn NMR and X-ray studies support the intramolecular donor-acceptor coordination between tin and nitrogen atoms in the stannanes. For the first time the J(15N-117/119Sn) coupling constant values in coordinated tin hydrides clearly point to a coordination number of the tin larger than four.