Synthesis of 2-Substituted 1,3-Butadienes by Cross-coupling Reaction of 2-(1,3-Butadienyl)magnesium Chloride with Alkyl or Aryl Iodides

The cross-coupling reactions of 2-(1,3-butadienyl)magnesium chloride (1) with aryl and alkyl iodides were investigated in the presence of transition metal catalysts. Tetrakis(triphenylphosphine)palladium(0) catalyzes the cross-coupling reactions of 1 with aryl iodides, and copper (I) iodide catalyzes the reaction with alkyl iodides. These cross-coupling reactions offer convenient routes for the synthesis of 2-substituted 1,3-butadienes.