GERMA-PHOSPHINES AND STANNA-PHOSPHINES FROM THE INSERTION OF GERMYLENES AND STANNYLENES INTO P-CL BONDS

The bis (amino) germylenes and -stannylenes 1-4 (Me2Si(NtBu)2M, M=Ge(1 ),Sn(2);(MeSi)2(NtBu)4M, M=Ge(3), Sn(4) insert into the P-Cl bonds of aryldichlorphosphine R-PCl2 (R=Ph, Mes) . While 1 may insert into one or two P-Cl bonds, depending on the molar ratios of 1 to R-PCl2, formi ng Me2Si(NtBu)2Ge(Cl)P(Cl)R (5) or (Me2Si(NtBu)2-Ge(Cl)]2P-R (6), 2 gi ves exclusively the diinsertion product [Me2Si(NtBu)2Sn(Cl)]2P-R (7). The sterically more hindered stannylene 4 inserts only into one P-Cl b ond forming (MeSi)2(NtBu)4Sn(Cl)P(Cl)R (8). With the exception of 6 al l insertion products, 5-8, are unstable and decompose via different in termediates which can be identified by H-1- and P-31-NMR to cyclic pho sphines (RP). (n = 4, 5, 6), Me2Si(NtBu)2MCl2 or (MeSi)2(NtBu)4MCl2, r espectively.