CuI/l-Proline-Catalyzed Coupling Reactions of Vinyl Bromides with Activated Methylene Compounds

The Ullmann-type coupling reaction of vinyl bromides and activated methylene compounds under CuI/l-proline in DMSO, at 90 °C in the presence of Cs2CO3 gives the corresponding vinyl compounds in moderate to good yields. This is a good method for preparing compounds with multiple functional groups including double bonds, carbonyls, and/or esters.