Experimental and Computational Studies on Cp*<sup>Cy</sup>Rh(III)/KOPiv-Catalyzed Intramolecular Dehydrogenative Cross-Couplings for Building Eight-Membered Sultam/Lactam Frameworks
作者:Liping Li、Hui Gao、Ming Sun、Zhi Zhou、Wei Yi
DOI:10.1021/acs.orglett.0c01823
日期:2020.7.17
is an unusual Cp*CyRh(III)-catalyzed intramolecular site-specific aryl C–H annulation, a highly chemoselective protocol providing direct access to eight-membered sultams/lactams with broad substrate/functional group tolerance. Experimental and computational studies reveal that such a transformation involves a unique PivOH-assisted aryl C–H activation/alkene insertion/β-H elimination/hydrogen-transfer
Rh-Catalyzed Cycloisomerization of 1,7-Ene-Dienes to Synthesize <i>trans</i>-Divinylpiperidines: A Formal Intramolecular Addition Reaction of Allylic C–H Bond into Dienes
An originally designed Rh-catalyzed [4 + 2] cycloaddition reaction of nitrogen-tethered 1,7-ene-dienes turned out to be a cycloisomerization reaction, which involves allylic C-H activation/alkene insertion into Rh-H bond/reductive elimination processes. Deuterium labeling experiments gave support to the proposed mechanism. This unexpected cycloisomerization reaction provides an efficient way to synthesize