C−H Methylation of Iminoamido Heterocycles with Sulfur Ylides**
作者:Prithwish Ghosh、Na Yeon Kwon、Saegun Kim、Sangil Han、Suk Hun Lee、Won An、Neeraj Kumar Mishra、Soo Bong Han、In Su Kim
DOI:10.1002/anie.202010958
日期:2021.1.4
The direct methylation of N‐heterocycles is an important transformation for the advancement of pharmaceuticals, agrochemicals, functional materials, and other chemical entities. Herein, the unprecedented C(sp2)‐H methylation of iminoamido heterocycles as nucleoside base analogues is described. Notably, trimethylsulfoxonium salt was employed as a methylating agent under aqueous conditions. A wide substrate
Cross-Coupling of α-Carbonyl Sulfoxonium Ylides with C−H Bonds
作者:Manuel Barday、Christopher Janot、Nathan R. Halcovitch、James Muir、Christophe Aïssa
DOI:10.1002/anie.201706804
日期:2017.10.9
non‐nucleophilic substrates using α‐carbonylsulfoxoniumylides has not been so far investigated, despite the potential safety advantages that such reagents would provide over either diazo compounds or their in situ precursors. Described herein are the cross‐coupling reactions of sulfoxoniumylides with C(sp2)−H bonds of arenes and heteroarenes in the presence of a rhodium catalyst. The reaction proceeds by a succession
cycloadditions, and the utilization of their recently realized reactivities to construct new cyclic architectures is of great significance in modern synthetic chemistry. Herein, a palladium‐catalyzed, visible‐light‐driven, asymmetric [5+2] cycloaddition of VCPs with α‐diazoketones is accomplished by switching the reactivity of the Pd‐containing dipolar intermediate from an all‐carbon 1,3‐dipole to an oxo‐1