Michael Addition of Allenoates to Electron-Deficient Olefins: Facile Synthesis of 2-Alkynyl-Substituted Glutaric Acid Derivatives
作者:Le-Ping Liu、Bo Xu、Gerald B. Hammond
DOI:10.1021/ol801411b
日期:2008.9.1
A Michaeladdition of allenoates to electron-deficientolefins was mediated efficiently by a catalytic amount of commercial tetra-n-butylammonium fluoride (TBAF) under mild conditions. And 2-alkynyl substituted glutaric acid derivatives, which may be potential building blocks in organic synthesis, were obtained in good to excellent yields from these reactions. The mechanism for the Michael addition
Efficient Synthesis of γ-Keto Esters through Neighboring Carbonyl Group-Assisted Regioselective Hydration of 3-Alkynoates
作者:Weibo Wang、Bo Xu、Gerald B. Hammond
DOI:10.1021/jo802450n
日期:2009.2.20
The Au(III)-catalyzed hydration of 3-alkynoates led to a practical one-step synthesis of gamma-keto esters in high yields, through a carbonyl group participation enabled by a favored 5-endodig cyclization. This mild-aqueous ethanol, room temperature, and atom-economical method has been used effectively with a wide range of substrates. Using the same conditions, a 2-alkynoate produced the corresponding beta-keto ester in high yield.