Ready oxidative addition of an alkyl or aryl halide to a tin(II) alkyl or amide; evidence for a free-radical pathway

Abstract

The addition of an alkyl or phenyl halide RX to Sn[CH(SiMe₃)₂]₂(X = Cl, Br, or I) or Sn[N(SiMe₃)₂]₂(X = Br or I) in n-hexane at 20 °C readily affords the 1 : 1-adducts (or 1:2-adduct for RX = CH₂Br₂ or CH₂I₂) which shows two sets of diastereotopically distinct Me₃Si₃ groups for Sn[CH(SiMe₃)₂]₂(X)R but not the nitrogen analogue; optical-activity and e.s.r data suggest a free-radical mechanism with ·SnY₂(X) and R· as intermediatesd [Y =(Me₃Si)₂CH or (Me₃Si)₂N].