Novel Alternative for the N<i>−</i>N Bond Formation through a PIFA-Mediated Oxidative Cyclization and Its Application to the Synthesis of Indazol-3-ones
The synthesis of a series of N,N‘-disubstituted indazolone derivatives starting from methyl anthranilates is presented. This general approach features a novel and easy way for access to the target N-heterocycles by formation of a new N−N single bond. The key cyclization step embraces the formation of an N-acylnitrenium intermediate, mediated by the hypervalent iodine reagent PIFA, and its succeeding
Iodine-Promoted Oxidative Cyclization of Acylated and Alkylated Derivatives from Epoxides toward the Synthesis of Aza Heterocycles
作者:Alageswaran Jayaram、Karthick Govindan、Vijaya Raghavan Kannan、Vijay Thavasianandam Seenivasan、Nian-Qi Chen、Wei-Yu Lin
DOI:10.1021/acs.joc.2c02802
日期:2023.2.3
A new method for directly synthesizing acylated and alkylated quinazoline derivatives by the epoxide ring-opening reaction in the presence of I2/DMSO with 2-aminobenzamide is described herein. The developed mild protocol is efficient and displays a wide variety of functional group tolerance and substrate-controlled high selectivity, and the application of a continuous flow technique allows for faster