Hypervalent-Iodine-Mediated Formation of Epoxides from Carbon(sp<sup>2</sup>)–Carbon(sp<sup>3</sup>) Single Bonds
作者:Shan Jiang、Tai-Shan Yan、Yong-Chao Han、Li-Qian Cui、Xiao-Song Xue、Chi Zhang
DOI:10.1021/acs.joc.7b00883
日期:2017.11.17
We have developed an efficient method for direct formation of epoxide groups from carbon(sp2)–carbon(sp3) single bonds of β-keto esters; the reaction is mediated by the water-soluble hypervalent iodine(V) reagent AIBX (5-trimethylammonio-1,3-dioxo-1,3-dihydro-1λ5-benzo[d][1,2]iodoxol-1-ol anion). On the basis of the results of density functional theory calculations and experimental studies, we propose
我们已经开发出一种有效的方法,可以从β-酮酸酯的碳(sp 2)-碳(sp 3)单键直接形成环氧基团。该反应通过水溶性高价碘(V)试剂AIBX(5-三甲基铵- 1,3-二氧代-1,3-二氢- 1λ介导的5 -苯并[ d ] [1,2] iodoxol -1-醇阴离子)。基于密度泛函理论计算和实验研究的结果,我们建议反应通过两阶段机理进行,该机理涉及β-酮酸酯底物的脱氢和所得烯酮中间体的环氧化。限速步骤是提取β'-C–H(计算的活化自由能,24.5 kcal / mol)。