Electronic and Steric Control of Regioselectivities in Rh(I)-Catalyzed (5 + 2) Cycloadditions: Experiment and Theory
作者:Peng Liu、Lauren E. Sirois、Paul Ha-Yeon Cheong、Zhi-Xiang Yu、Ingo V. Hartung、Heiko Rieck、Paul A. Wender、K. N. Houk
DOI:10.1021/ja103253d
日期:2010.7.28
The first studies on the regioselectivity of Rh(I)-catalyzed (5 + 2) cycloadditions between vinylcyclopropanes (VCPs) and alkynes have been conducted experimentally and analyzed using density functional theory (DFT). The previously unexplored regiochemical consequences for this catalytic, intermolecular cycloaddition were determined by studying the reactions of several substituted VCPs with a range
Cyclopentenones from 1,2-disiloxycyclobutene via silylated 1-vinylcylopropanols. Application to the synthesis of dihydrojasmone and cis-jasmone
作者:J. Salaün、Y. Almirantis
DOI:10.1016/s0040-4020(01)91969-6
日期:1983.1
An effective synthesis of 2,3-disubstituted 2-cyclopentenones involves C4→C3 ring contraction of the readily available 1,2-disiloxycyclobutene followed by thermal C3→C5 ring enlargement of trimethylsiloxyvinyl-cyclopropanes. To illustrate the convenience of this new approach the total syntheses of 2-methyl-3-p-tolyl-2-cyclopentenone, dihydrojasmone. and cis-jasmone are reported.