Heterogeneous Suzuki–Miyaura coupling of heteroaryl ester <i>via</i> chemoselective C(acyl)–O bond activation
作者:Hongpeng Ma、Chaolumen Bai、Yong-Sheng Bao
DOI:10.1039/c9ra02394a
日期:——
A site-selective supported palladium nanoparticle catalyzed Suzuki–Miyaura cross-coupling reaction with heteroaryl esters and arylboronic acids as coupling partners was developed. This methodology provides a heterogeneous catalytic route for aryl ketone formation via C(acyl)–O bond activation of esters by successful suppression of the undesired decarbonylation phenomenon. The catalyst can be reused
[reaction: see text] The palladium-catalyzed coupling reaction of 2-pyridyl esters with organoboroncompounds is described. The reaction is compatible with various functional groups and proceeds under mild reaction conditions. The coordination of the nitrogen atom to Pd is a key step for efficient reaction.
A novel metal- and catalyst-free dearomative reaction of 2-oxypyridines to construct gem-difluoromethylenated N-substituted 2-pyridones has been developed. The reaction involves an attractive acyl rearrangement from O to CF2 of difluorocarbene-derived pyridinium ylides, which provides a new strategy for the direct introduction of the gem-difluoromethylene group with high efficiency and selectivity as