作者:Dong Zhou、Clemens Reiche、Mrinmoy Nag、John A. Soderquist、Peter P. Gaspar
DOI:10.1021/om800541f
日期:2009.4.27
1,1-Diorgano-1-stannacyclopent-3-enes have been synthesized by condensation in THF of magnesium complexes of 1,3-dienes and dichlorodiorganostannanes. 1, 1-Dimethyl-, 1, 1-di-n-butyl-,1, 1-di-tert-butyl-, and 1,1-diphenyl-1-stannacyclopent-3-enes and 1,1,3,4-tetramethyl-, 1,1-di-tert-butyl-3,4-dimethyl-, and 3,4-dimethyl-1,1-diphenyl-1-stannacyclopent-3-enes were prepared. Kinetic studies of the pyrolysis. at temperatures as low as 75 degrees C of several of these stannacyclopent-3-enes resulted in their first-order disappearance, consistent with a unimolecular dissociation to the corresponding stannylene and diene. Activation parameters are reported. Trapping of dimethylstannylene by dienes was overwhelmed by oligomerization of Me2Sn::, but for t-Bu2Sn: a high yield of diene adduct was obtained. The dimethylstannylene oligomer(s) functioned as stannylenoids and were responsible for several reactions previously attributed to free Me2Sn:. cyclo-(t-Bu2Sn)(4) may also function as a stannylenoid.