手性芳基烯丙基醚类化合物是一类重要的结构骨架,其广泛存在于天然产物和药物活性分子结构中。以设计合成的MBH(Morita-Baylis-Hillman)碳酸苯酯作为反应底物,其在亲核手性催化剂作用下脱去一分子CO 2,生成了一系列含有各种取代基的手...手性芳基烯丙基醚类化合物是一类重要的结构骨架,其广泛存在于天然产物和药物活性分子结构中。以设计合成的MBH(Morita-Baylis-Hillman)碳酸苯酯作为反应底物,其在亲核手性催化剂作用下脱去一分子CO 2,生成了一系列含有各种取代基的手性的芳基烯丙基醚化合物。产率高达95%,对映选择性高达90%。产物结构经1 H NMR和13 C NMR鉴定正确。展开更多
The mechanisms of gold（I）-catalyzed cycloaddition of 1-（1-alkynyl） cyclopropyl ketones with nucleophiles have been investi- gated using density functional theory calculations at the B3LYP/6-31G （d, p） level of t...The mechanisms of gold（I）-catalyzed cycloaddition of 1-（1-alkynyl） cyclopropyl ketones with nucleophiles have been investi- gated using density functional theory calculations at the B3LYP/6-31G （d, p） level of theory. A polarizable continuum model （PCM） has been established in order to evaluate the effects of solvents on the reactions. The results of the calculations indicate that the first step of the catalytic cycle is the cyclization of the carbonyl oxygen onto the triple bond which forms a new and stable resonance structure of an oxonium ion and a carbocation intermediate. The subsequent ring expansion step results in the formation of the final product and regeneration of the catalyst. Furthermore, the regioselectivity and effect of substituents has been discussed, including an analysis of energy, bond length, and natural bond orbital （NBO） charge distributions in the rate-determining step. Our computational results are consistent with earlier experimental observations.展开更多
文摘手性芳基烯丙基醚类化合物是一类重要的结构骨架,其广泛存在于天然产物和药物活性分子结构中。以设计合成的MBH(Morita-Baylis-Hillman)碳酸苯酯作为反应底物,其在亲核手性催化剂作用下脱去一分子CO 2,生成了一系列含有各种取代基的手性的芳基烯丙基醚化合物。产率高达95%,对映选择性高达90%。产物结构经1 H NMR和13 C NMR鉴定正确。
基金supported by the Natural Science Foundation of Gansu Province (10710RJZA114)
文摘The mechanisms of gold（I）-catalyzed cycloaddition of 1-（1-alkynyl） cyclopropyl ketones with nucleophiles have been investi- gated using density functional theory calculations at the B3LYP/6-31G （d, p） level of theory. A polarizable continuum model （PCM） has been established in order to evaluate the effects of solvents on the reactions. The results of the calculations indicate that the first step of the catalytic cycle is the cyclization of the carbonyl oxygen onto the triple bond which forms a new and stable resonance structure of an oxonium ion and a carbocation intermediate. The subsequent ring expansion step results in the formation of the final product and regeneration of the catalyst. Furthermore, the regioselectivity and effect of substituents has been discussed, including an analysis of energy, bond length, and natural bond orbital （NBO） charge distributions in the rate-determining step. Our computational results are consistent with earlier experimental observations.
