Acid-Catalyzed Direct Conjugate Alkenylation of α,β-Unsaturated Ketones

摘要

The conjugate addition reaction to α,β-unsaturated carbonyl compounds is one of the most fundamental reactions in organic chemistry. It is a powerful and reliable tool for the formation of carbon-carbon bonds. Numerous C—C bond-forming conjugate addition reactions involve the nucleophilic attack of a carbanion species (known as Michael-type reactions), thus generally affording stoichiometric amounts of metal salts as waste products. Nowadays, from an environmental point of view, the reduction of waste in organic reactions is one of the most important issues to solve. For alkenylation reactions, alkenylmetal reagents are often used in the conjugate alkenylation of enones (Scheme la).