Microwave-assisted sonogashira-type coupling of terminal alkynes and aryl boronic acid

Abstract

A microwave reactor for chemical synthesis have been designed and constructed. Microwave irradiation provided a selective heating to the reaction mixture. The main advantage of use microwave-assisted is reaction acceleration, yield improvement, and safe. An easy, rapid methodology for microwave-assisted Sonogashira-type coupling reactions of arylboronic acids with electron-deficient terminal alkynes in absence of ligand under ambient atmosphere is described. The reactions used low loading palladium-atalyzed in silver-assisted system, K2CO3 as base, and THF as solvent to afford the corresponding product in moderate-high yield in 20 min with only 100 Watt microwave power. Thus, it represents a simple and alternative method for conventional heating.