LASER-POWERED HOMOGENEOUS PYROLYSIS OF 4-SILASPIRO[3,3]HEPTANE - A SOURCE FOR 2-SILAALLENE AND ITS POLYMER

Continuous-wave CO2 laser-photosensitized (SF6) decomposition of 4-sil aspiro[3,3]heptane is dominated by the transient formation and polymer ization of 2-silaallene. The first experimental evidence for 2-silaall ene has been achieved via scavenging with alcohols ROH (R = CH3, CF3CH 2) to afford dialkoxy(dimethyl)silanes, (RO)(2)Si(CH3)(2). ESCA analys is of the polymer demonstrates SiC2 stoichiometry and indicates the in corporation of oxygen, which may be explained by reaction of the resid ual Si=C bonds with air.