Microwave-assisted unprotected Sonogashira reaction in water for the synthesis of polysubstituted aromatic acetylene compounds

A microwave-assisted, efficient and rapid Sonogashira reaction was developed for the synthesis of polysubstituted aromatic alkynes. The reaction was made environmentally friendly and easy to perform by replacing the traditional amine solvents with water. The optimized reaction conditions yielded the products with high yields, while reducing the dependence on anaerobic reaction conditions with no inert gas protection. The reaction also achieved the product on the milligram level, overcoming the problem of TMSA volatilization in small-scale reactions. The environmentally friendly reaction solvent, mild reaction conditions, high reaction yields and short reaction time made the reaction highly promising for various applications, especially for synthesizing porous aromatic frameworks. A series of porous aromatic framework material units were obtained by performing microwave-assisted Sonogashira reactions in water without inert gas protection.