Highly efficient synthesis of 4-trifluoromethylfuran derivatives via a sequential deprotection-annulation reaction

(E)-O-protected-2-trifluoromethyl-1-bromo-1-substituted allylic alcohol reacted with terminal alkynes under Sonogashira reaction condition to give the corresponding (E)-2-en-4-ynoic alcohol derivatives, which was further converted to the corresponding 4-trifluoromethylfuran derivatives via a sequential deprotection-annulation reaction in moderate to excellent yields.