Radical-Based Synthesis of Terpenoids. Stereoselectivity in the Trapping of Radicals from Cyclization of 3-(1-Ethoxy-2-haloethoxy)cyclohexenes
作者:Hajime Nagano、Keiko Yamada、Noriko Hazeki、Yukie Mori、Tsuneo Hirano
DOI:10.1246/bcsj.65.2421
日期:1992.9
Stereoselectivity in the intermolecular trapping of the bicyclic radical intermediates from cyclization of 3-(1-ethoxy-2-haloethoxy)cyclohexenes with methyl acrylate was found to be affected remarkably by the conformation of the radical intermediates. The optimized conformers of 8-methoxy-7-oxabicyclo[4.3.0]non-2-yl radicals, models for the radical intermediates, were obtained by PM3 RHF molecular orbital calculations, and the stereoselectivity was analyzed in detail.
研究发现,3-(1-乙氧基-2-卤乙氧基)环己烯与丙烯酸甲酯环化产生的双环自由基中间体的分子间立体选择性明显受到自由基中间体构象的影响。通过 PM3 RHF 分子轨道计算得到了作为自由基中间体模型的 8-甲氧基-7-氧杂双环[4.3.0]壬-2-基自由基的优化构象,并对其立体选择性进行了详细分析。