Deoxygenative α-alkylation and α-arylation of 1,2-dicarbonyls
作者:Shengfei Jin、Hang T. Dang、Graham C. Haug、Viet D. Nguyen、Hadi D. Arman、Oleg V. Larionov
DOI:10.1039/d0sc03118f
日期:——
challenging but synthetically indispensable approach to α-branched carbonyl motifs that are widely represented among drugs, natural products, and synthetic intermediates. Here, we describe a simple approach to generation of boron enolates in the absence of strong bases that allows for introduction of both α-alkyl and α-aryl groups in a reaction of readily accessible 1,2-dicarbonyls and organoboranes. Obviation
Photocatalyzed Direct α‐Alkylation of Esters Using Styrenes
作者:Pengzhi Wang、Anna V. Bay、Emelia J. Farnam、Karl A. Scheidt
DOI:10.1002/adsc.202300253
日期:2023.7.18
Abstract
A mild photocatalyzed approach to achieve the α‐alkylation of esters via formation of an α ‐radical is disclosed here. Cesium enolates of esters were generated in situ using Cs2CO3 as a base. A subsequent photocatalyzed oxidation at the α‐carbon of these enolates produced an α‐radical that was added into activated alkenes. This is the first example accessing the α‐carbon radical of esters in photoredox catalyed transformations.