Germa- and stannaphosphines from the insertion of germylenes and stannylenes into P-Cl-bonds

Abstract

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, forming Me2Si(NtBu)2Ge(Cl)P(Cl)R (_5) or [Me2Si (NtBu)2-Ge(Cl)]2P-R (_6), _2 gives exclusively the diinsertion product [Me2Si (NtBu)2Sn(Cl)]2P-R (_7). The sterically more hindered stannylene _4 inserts only into one P-Cl bond forming (MeSi)2(NtBu)4Sn(Cl)P(Cl)R (_8). With the exception of _6 all insertion products, _5-_8, are unstable and decompose via different intermediates which can be identified by 1H- and 31P-NMR to cyclic phosphines (RP)n (n=4,5,6), Me2Si(NtBu)2MCl2 or (MeSi)2(NtBu)4MCl2, respectively.