Zhang Guan-Yu, Lin Mu, Yu Zhi-Xiang
Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, P. R. China.
Chem Asian J. 2023 Apr 3;18(7):e202300032. doi: 10.1002/asia.202300032. Epub 2023 Feb 22.
DFT calculations have been applied to study the mechanisms of [3+2] and [3+2+1] reactions of ene/yne-vinylcyclopropanes (shorted as ene/yne-VCPs). The [3+2] reactions of ene/yne-VCPs start from C-C cleavage of cyclopropane (CP cleavage) to form six-membered rhodacycle, followed by alkene/alkyne insertion and reductive elimination. The [3+2+1] reactions have two competing pathways, one is the [3+2+1] pathway (CP cleavage, ene/yne insertion, CO insertion and reductive elimination) and the other is the [3+1+2] pathway (CP cleavage, CO insertion, ene/yne insertion and reductive elimination). The length of tether in substrates affects the ene/yne insertion steps in these cycloadditions, making some reactions fail or changing the reaction pathways. The reasons for these tether length effects are discussed.
密度泛函理论（DFT）计算已被用于研究烯/炔基乙烯基环丙烷（简称为烯/炔-VCPs）的[3+2]和[3+2+1]反应机理。烯/炔-VCPs的[3+2]反应从环丙烷的C-C键断裂（环丙烷断裂）开始，形成六元铑环，随后烯烃/炔烃插入并进行还原消除。[3+2+1]反应有两条竞争途径，一条是[3+2+1]途径（环丙烷断裂、烯/炔插入、CO插入和还原消除），另一条是[3+1+2]途径（环丙烷断裂、CO插入、烯/炔插入和还原消除）。底物中连接链的长度会影响这些环加成反应中的烯/炔插入步骤，导致一些反应失败或改变反应途径。本文讨论了这些连接链长度效应的原因。
