Transition-Metal-Free Regioselective Alkylation of Quinoline N-Oxides via Oxidative Alkyl Migration and C−C Bond Cleavage of tert-/sec-Alcohols
作者:Chiranjit Sen、Subhash C. Ghosh
DOI:10.1002/adsc.201701330
日期:2018.3.1
An unprecedented C2‐alkylation of quinoline N‐oxide derivatives via C−C bond activation of tert‐ and sec‐alkyl alcohol is described using hypervalent iodine (III) reagent PhI(OAc)2 (PIDA). This regioselective alkylation using mild hypervalent iodine reagents is more practical, operationally simple and transition metal free. The reaction proceeds efficiently with a broad range of substrates including
Benzylation of heterocyclic N-oxides via direct oxidative cross-dehydrogenative coupling with toluene derivatives
作者:L. Wan、K. Qiao、X. N. Sun、Z. C. Di、Z. Fang、Z. J. Li、K. Guo
DOI:10.1039/c6nj02560a
日期:——
A novel cross-dehydrogenative coupling (CDC) of heterocyclic N-oxides with toluene derivatives has been discussed, allowing for the facile synthesis of a broad range of structurally diverse C1-benzyl quinoline N-oxides, isoquinoline N-oxides and pyridine N-oxides, including two methylated quinoline N-oxides in particular. This protocol not only extends the application of toluenes in synthetic organic
C2-Selective C–H Methylation of Heterocyclic <i>N</i>-Oxides with Sulfonium Ylides
作者:Won An、Su Bin Choi、Namhoon Kim、Na Yeon Kwon、Prithwish Ghosh、Sang Hoon Han、Neeraj Kumar Mishra、Sangil Han、Sungwoo Hong、In Su Kim
DOI:10.1021/acs.orglett.0c03403
日期:2020.11.20
A redox-neutral C2-selective methylation of heterocyclicN-oxides with sulfonium ylides is described herein. This report presents unprecedented findings for the utility of sulfonium ylides as the methylation source of N-heterocycles beyond the Corey–Chaykovsky reaction. Intriguingly, pyrrolidine plays a significant role in minimizing the reductive C2-methylation process. This method is characterized