Silver-catalyzed activation of internal propargylic alcohols in supercritical carbon dioxide: efficient and eco-friendly synthesis of 4-alkylidene-1,3-oxazolidin-2-ones

The silver-catalyzed cycloaddition reactions of carbon dioxide with internal propargylic alcohols and primary amines under supercritical conditions give 4-alkylene-1,3-oxazolidin-2-ones in good to excellent yields. The optimized conditions are to use an alcohol (2 mmol), an amine (2 mmol), silver acetate (0.1 mmol), and carbon dioxide (8 MPa) at 120 °C.