Transition-metal-free heterocyclization of 1,3-diynes with nitriles in the presence of aqueous potassium hydroxide: Synthesis of 2,4-disubstituted 5-[(E)-2-Phenylethenyl]-1,3-oxazoles

摘要

A transition-metal-free heterocyclization of 1,3-diynes and nitriles in the presence of either aqueous potassium hydroxide or cesium hydroxide in 1,4-dioxane at 100 °C was realized. This method provided stereoselectively 2,4-disubstituted 5-[(E)-2-phenylethenyl]-1,3-oxazoles in moderate to good yields.