公开了用 Cu(NO 3 ) 2和 KI 以区域选择性和立体选择性方式对乙烯基环丙烷进行直接硝化,以有效地得到硝基烯烃,其中保留了环丙烷骨架。给定的方法可以扩展到其他乙烯基环以及具有广泛底物范围、良好功能耐受性和高效合成模块化的生物分子衍生物。进一步的转化表明所获得的产品是有机合成中的通用构建块。所提出的离子途径可以解释未接触的小环和反应过程中 KI 的影响。
Convergent Synthesis of Dihydropyrans from Catalytic Three-Component Reactions of Vinylcyclopropanes, Diazoesters, and Diphenyl Sulfoxide
作者:Ya-Lin Zhang、Rui-Ting Guo、Heng Luo、Xin-Shen Liang、Xiao-Chen Wang
DOI:10.1021/acs.orglett.0c01992
日期:2020.7.17
three-component reaction of vinylcyclopropanes, diazoesters, and diphenyl sulfoxide has been developed. The reaction gives polysubstituted dihydropyrans as the reactionproducts. Mechanistic studies indicate that isomerization of vinylcyclopropanes gives conjugated dienes, which then undergo [4 + 2]-cycloaddition with vicinaltricarbonyl compounds generated by oxygen atom transfer from diphenyl sulfoxide
Iridium Catalyzed Carbocyclizations: Efficient (5+2) Cycloadditions of Vinylcyclopropanes and Alkynes
作者:Michaela-Christina Melcher、Henrik von Wachenfeldt、Anders Sundin、Daniel Strand
DOI:10.1002/chem.201405729
日期:2015.1.7
Third‐row transition metal catalysts remain a largely untapped resource in cycloaddition reactions for the formation of medium‐sized rings. Herein, we report the first examples of iridium‐catalyzed inter‐ and intramolecular vinylcyclopropane (VCP)–alkyne (5+2) cycloadditions. DFT modeling suggests that catalysis by iridium(I) proceeds through a mechanism similar to that previously reported for rhodium(I)‐catalyzed
Highly Efficient, Facile, Room Temperature Intermolecular [5 + 2] Cycloadditions Catalyzed by Cationic Rhodium(I): One Step to Cycloheptenes and Their Libraries
作者:Paul A. Wender、Lauren E. Sirois、René T. Stemmler、Travis J. Williams
DOI:10.1021/ol100337m
日期:2010.4.2
A cationic rhodium(I) complex-[(C(10)H(8))Rh(cod)](+) SbF(6)(-)-Catalyzes the remarkably efficient intermolecular [5 + 2] cycloaddition of vinylcyclopropanes (VCPs) and various alkynes, providing cycloheptene cycloadducts in excellent yields in minutes at room temperature. The efficacy and selectivity of this catalyst are also shown in a novel diversification strategy, affording a cycloadduct library in one step from nine commercially available components.
Rh(I)-Catalyzed [5 + 1] Cycloaddition of Vinylcyclopropanes and CO for the Synthesis of α,β- and β,γ-Cyclohexenones
作者:Guo-Jie Jiang、Xu-Fei Fu、Qian Li、Zhi-Xiang Yu
DOI:10.1021/ol2031526
日期:2012.2.3
A cationic Rh(I)-catalyzed [5 + 1] cycloaddition of vinylcyclopropanes and CO has been developed, affording either beta,gamma-cyclohexenones as major products or alpha,beta-cyclohexenones exclusively, under different reaction conditions.