Transition-Metal-Free Coupling of Alkynes with α-Bromo Carbonyl Compounds: An Efficient Approach towards β,γ-Alkynoates and Allenoates
A direct transition-metal-free coupling between alkynes and α-bromo carbonyl compounds has been developed with ultraviolet (UV) light in aqueous media. This method represents a facile approach to synthetically useful β,γ-alkynyl esters and amides stereoselectively from two readily available starting materials. As an example of the synthetic application of the products, the alkynyl esters were readily converted into allenoates. Time for UV! A direct coupling between alkynes and α-bromo compounds has been developed with ultraviolet light in aqueous media (see scheme). This method represents a facile approach to synthetically useful β,γ-alkynyl esters and amides stereoselectively from two readily available starting materials.