Synergistic Pd(0)/Rh(II) Dual Catalytic [6 + 3] Dipolar Cycloaddition for the Synthesis of Monocyclic Nine-Membered <i>N,O</i>-Heterocycles and Their Alder-ene Rearrangement to Fused Bicyclic Compounds
作者:Kyu Ree Lee、Subin Ahn、Sang-gi Lee
DOI:10.1021/acs.orglett.1c01135
日期:2021.5.7
challenge in organic synthesis. Herein we report the synergistic palladium(0)/rhodium(II) dual catalytic cycloaddition of vinylpropylene carbonates with N-sulfonyl-1,2,3-triazoles to afford monocyclic nine-membered N,O-heterocycles. The catalytically generated 1,6-dipole-equivalent zwitterionic π-allyl palladium(II) complex and the 1,3-dipole-equivalent α-imino rhodium(II) carbenoid intermediate react
单环中型N,O-杂环的催化结构代表了有机合成中的巨大挑战。在本文中,我们报道了乙烯基丙烯碳酸酯与N-磺酰基-1,2,3-三唑的协同钯(0)/铑(II)双催化环加成反应,以提供单环九元N,O-杂环。催化生成的1,6-偶极当量两性离子π-烯丙基钯(II)配合物和1,3-偶极当量α-亚氨基铑(II)类胡萝卜素中间体在正式的[6 + 3]双极中相互反应环加成反应可提供九元恶唑酮,可将其转变为顺式跨环的Alder-ene重排稠合的[4.3.0]双环化合物。串联一锅环加成/ Alder-ene重排序列也是可能的。