A base-initiated thioesterification of amides with various thiols is reported. This reaction can take place efficiently under metal-free and air-atmospheric conditions, and provides a facile and practically useful approach to the synthesis of valuable acyl thioesters.
An interesting procedure for thioester synthesis via nickel-catalyzed thiocarbonylation of arylboronic acid with sulfonyl chlorides as the sulfur source has been explored. Using Mo(CO)6 as a solid CO surrogate and reductant, a broad range of thioesters were obtained in moderate to good yields with good functional group tolerance.
Role of Aggregates in Claisen Acylation Reactions of Imidazole, Pyrazole, and Thioesters with Lithium Enolates in THF<sup>1</sup>
作者:Andrew Streitwieser、Simon S.-W Leung、Yeong-Joon Kim
DOI:10.1021/ol990604b
日期:1999.7.1
Although phenyl esters react with both monomers and dimers or tetramers of two lithium enolates in THF, the reactions of phenyl thiobenzoates are relatively much faster with the monomers. Similarly, imidazole esters react primarily with the monomers but pyrazole esters react with monomers and aggregates. The results are rationalized by a mechanism in which coordination with two lithium cations within