Palladium-catalyzed hydrophenylation of bicyclic alkenes
作者:Peter Mayo、William Tam
DOI:10.1016/s0040-4020(02)01277-2
日期:2002.11
Palladium-catalyzed hydrophenylation reactions of bicyclic alkenes were investigated. These reactions were found to be completely chemo- and stereoselective, giving only exo products on the less substituted double bonds of bicyclic alkenes in moderate to good yields. For unsymmetrical bicyclic alkenes, regioselectivities of 52:48 to 100:0 were observed with various substituents on the bicyclic alkenes
Ring-opening metathesis–cross-metathesis reactions (ROM–CM) of substituted norbornadienes and norbornenes
作者:Peter Mayo、William Tam
DOI:10.1016/s0040-4020(02)01276-0
日期:2002.11
This study provides an efficient method for the stereoselective synthesis of highly substituted cyclopentenoids. Long-range electronic effect of a remote substituent on unsymmetrical norbornenes in the ROM–CM reactions was also investigated. Low levels of regioselectivities were observed (50:50 to 69:31) with various remote substituents on the norbornenes.
Reactivity of the alkene component in the ruthenium-catalyzed [2+2] cycloaddition between an alkene and an alkyne: Part 2
作者:Robert W Jordan、William Tam
DOI:10.1016/s0040-4039(02)01191-7
日期:2002.8
Ruthenium-catalyzed [2+2] cycloadditions of 2,3-disubstituted norbornadienes and 2-substituted norbornadienes with an alkyne were found to be highly chemo- and stereoselective with moderate level of regioselectivities and only small rate differences were observed with different substituents on the norbornadiene. (C) 2002 Elsevier Science Ltd. All rights reserved.
Heat of Hydrogenation of 1,5-Dehydroquadricyclane. A Computational and Experimental Study of a Highly Pyramidalized Alkene
作者:Rebecca L. Hoenigman、Shuji Kato、Veronica M. Bierbaum、Weston Thatcher Borden
DOI:10.1021/ja054720n
日期:2005.12.1
1*- apparently does not undergo a retro-Diels-Alder reaction is of particular interest. The B3LYP/6-31+G* optimized geometry of 1 suggests that the bonding in this alkene is partially delocalized, presumably because the highly pyramidalized double bond in 1 interacts with the distal cyclopropane bonds in a manner that eventually leads to a retro-Diels-Alder reaction. The good agreement of the B3LYP and