Cyclohexenol annulation via the alkoxy-accelerated rearrangement of vinylcyclobutanes
作者:Rick L. Danheiser、Carlos Martinez-Davila、Howard Sard
DOI:10.1016/s0040-4020(01)93268-5
日期:——
efficient method for the synthesis of 3-cyclohexenol derivatives. 2-Vinylcyclobutanones are prepared from α,β-unsaturated carbonyl compounds by the method of Trost and via [2 + 2]-cycloadditions of olefins and vinylketenes. Addition of hydride or alkyllithium reagents then generates 2-vinylcyclobutanol salts which directly rearrange to afford 3-cyclohexenols. The two methods constitute new [3 + 3]- and [4 +
Diels-Alder reactions of 2-Alkenylboranes and cis-1-alkenylboranes. Anomalous selectivity that allows a choice of regiochemistry
作者:Daniel A. Singleton、Kyeongsook Kim、Jose P. Martinez
DOI:10.1016/s0040-4039(00)93382-3
日期:1993.5
2-Alkenyl- and cis-1-alkenylboranes are highly reactive Diels-Alder dienophiles which display unusual selectivity patters. By taking advantage of a reversal of regiochemistry of reaction with alkenyldihalo- versus alkenyldialkylboranes, any desired regioisomeric product may be favored, usually with very high selectivity.