Catalyst-Dependent Chemoselective Formal Insertion of Diazo Compounds into C−C or C−H Bonds of 1,3-Dicarbonyl Compounds
作者:Zhaohong Liu、Paramasivam Sivaguru、Giuseppe Zanoni、Edward A. Anderson、Xihe Bi
DOI:10.1002/anie.201802834
日期:2018.7.16
one‐carbon insertion of diazo compounds into the C−C or C−H bonds of 1,3‐dicarbonyl species is reported. In the presence of silver(I) triflate, diazo insertion into the C(=O)−C bond of the 1,3‐dicarbonyl substrate leads to a 1,4‐dicarbonyl product containing an all‐carbon α‐quaternary center. This reaction constitutes the first example of an insertion of diazo‐derived carbenoids into acyclic C−C bonds. When
Iodine catalyzed C (sp(3))-H functionalization of tosylhydrazones with beta-enamino esters under visible light irradiation for the synthesis of trisubstituted pyrroles has been described. The present method is also applicable to a alpha-substituted tosylhydrazones to yield the tetra-substituted pyrroles.