Studies on Mercury(II)-Mediated Opening of Bi- and Tercyclopropane Arrays
摘要:
The first examples of the mercury(II)-mediated ring opening of bicyclopropane and tercyclopropane arrays have been investigated. The presence of an adjacent cyclopropyl group dramatically increased the rate of the mercury-mediated opening of the first cyclopropane in a cyclopropane array. In contrast to the mercury-mediated ring opening of monocyclopropanes which usually undergo a concerted ring-opening mechanism, electrophilic openings of cyclopropane arrays occurred through a stabilized, free carbocation. Excellent regio- and stereoselectivities were observed in the mercury-mediated intramolecular openings of the second cyclopropanes in the cyclopropane arrays, giving rise to the formation of enantiomerically pure, highly substituted tetrahydrofurans.
Studies on Mercury(II)-Mediated Opening of Bi- and Tercyclopropane Arrays
作者:Anthony G. M. Barrett、William Tam
DOI:10.1021/jo970464o
日期:1997.7.1
The first examples of the mercury(II)-mediated ring opening of bicyclopropane and tercyclopropane arrays have been investigated. The presence of an adjacent cyclopropyl group dramatically increased the rate of the mercury-mediated opening of the first cyclopropane in a cyclopropane array. In contrast to the mercury-mediated ring opening of monocyclopropanes which usually undergo a concerted ring-opening mechanism, electrophilic openings of cyclopropane arrays occurred through a stabilized, free carbocation. Excellent regio- and stereoselectivities were observed in the mercury-mediated intramolecular openings of the second cyclopropanes in the cyclopropane arrays, giving rise to the formation of enantiomerically pure, highly substituted tetrahydrofurans.