6-Exo and 7-endo photocyclization of αβ-unsaturated organosilicon ω-thiols
摘要:
The regioselectivity of cyclization of 3,3- and 4,4-dimethylsila-1-hexene-6-thiols upon UV-irradiation is reported. Ring closure involving the vinyl group at silicon results in the preferred formation of the exo-cyclic product, whereas a high and reversed regio- selectivity is observed when the cyclization reaction occurs via the allyl group at silicon.
作者:S. V. Kirpichenko、A. T. Abrosimova、A. I. Albanov、M. G. Voronkov
DOI:10.1023/a:1014275807004
日期:——
Unsaturated organosilicon amines [CH2=CH(CH2)(n)]Me2Si[(CH2)(m)NHPh] at the action of Hg(OAc)(2) in THF solution transform to corresponding heterocycles. Regioselectivity of this intramolecular electrophilic heterocyclization is defined by the position of double bond relatively to the silicon atom. This is caused by beta-effect of the silyl group.