Visible-light-induced cascade cyclization of N-acrylohydrazides toward functionalized pyrazolones and the application in drug modification

Abstract

A photocatalytic radical cascade cyclization of N-acryloylhydrazides with α-bromoketones was developed. A series of 4-(3-oxo-3-phenylpropyl)-1H-pyrazol-5(4H)-ones were formed in moderate to good yields.α-Bromo difluoroacetamides and 2-bromoacetonitrile were also suitable reaction partners. Late-stage modifications of a plenty many of drug molecules was also achieved through our strategy.