Tris(trimethylsilyl)methyltin oxinates and their conversion into bis-(trimethylsilyl)methyltin oxinates

Abstract

8-Hydroxyquinoline reacts in ethanol with organotin halides SnRX₃, SnR′RX₂, SnR′₂RX [where R′= Me or Ph; R =(Me₃Si)₃C; X = halide] to yield oxinate complexes [SnR(ox)₃], [Sn(OEt)R(ox)₂], [SnR′R(ox)₂], and [SnR′₂R(ox)]. The [SnR′R(ox)₂] complexes exist in two cis isomeric forms. When the di- or tri-oxinates are heated in ethanol nucleophilic cleavage of one trimethylsilyl group occurs yielding the bis(trimethylsilyl)methyl compounds, [Sn(OEt){CH(SiMe₃)₂}(ox)₂] and [SnR′{CH(SiMe₃)₂}(ox)₂]. The methyl complex has the structure cis-[SnMe{CH(SiMe₃)₂}(ox)₂] with nitrogen trans to both Sn–C bonds. Hydrobromic acid readily converts these oxinates into the corresponding bromides.