Consecutive Reactions of Vinylic Phosphonium Salts with Grignard Reagents Catalyzed by CuBr−Ag<sub>2</sub>CO<sub>3</sub> or CuBr−H<sub>2</sub>O ShenYanchang YaoJiangzhao 1996 Consecutive Reactions of Vinylic Phosphonium Salts with Grignard Reagents Catalyzed by CuBr−Ag<sub>2</sub>CO<sub>3</sub> or CuBr−H<sub>2</sub>O