in diethyl ether dropwise addn. of stannane in Et2O to LiCH2PMe2 in Et2O at -78°Cwith stirring, warming to room temp., stirring for 12 h; evapn. of solvent in vacuo, redissolution in pentane, filtn., washing residue with pentane (two times), evapn. of solvent in vacuo, fractionating in vacuo, elem. anal.;