Nano CaCO3: playing a special role in the monofunctionalization of calixarenes by epoxides

Abstract

It was found that nano CaCO₃ played an interesting role in the reaction of p-tert-butylcalixarene with epoxides. In the presence of nano CaCO₃, a monosubstituted calixarene, a β ring-opening product of epoxide, was obtained regioselectively in good yield. When normal CaCO₃ was used under the same conditions, the yield was less than 2%. The β ring-opening product of epichlorohydrin could convert to monoglycidyl calixarene by reacting with C₂H₅ONa in tetrahydrofuran at room temperature in moderate yield.