2‐Triorgano‐silyl, ‐germyl, ‐stannyl and ‐plumbyl derivatives of 1,3‐diisopropyl‐benzo‐1,3,2‐diazaborolidine and related compounds and their reactions with (η2‐C2H4)Pt(PPh3)2

摘要: A series of 1,3-diisopropyl-benzo-1,3,2-diazaborolidines 1-6 carrying ER3 substituents Group 14 at the boron atom (E = C, Si, Ge, Sn, Pb; R Me, Ph) have been prepared. Their molecular structures determined. As expected, B-E bond length increases along this series. Moreover, orientation isopropyl groups relative to ER 3 substituent is influenced by steric demand these substituents. The 11 B NMR data show a deshielding nucleus as atomic weight E increases. Oxidative addition reactions with (η 2 -C H 4 )Pt(PPh ) were successful only for bromo derivative 1 and trimethylstannyl 5a; they failed triphenylsilyl, triphenylgermyl triphenylstannyl compounds, indicating that effects play an important role in oxidative boryl-substituted bis(triphenylphosphane)platinum(II) complexes. triphenylplumbyl 6 reacted give cis- trans-diphenyl-bis(triphenylphosphane)platinum besides Ph(Ph Pb)Pt(PPh . Obviously, Pb-C more reactive than Pb-B bond. Cis-Platinum-boryl complexes also obtained from (Me N) B-SnMe B-GeMe while boranes tmpB(SnMe i Pr NB(SnMe unreactive.