Methode zur Herstellung von alpha, beta ungesättigten Ketolactonen

摘要

The present invention provides a method of preparing alpha , beta -unsaturated ketolactones which are useful for production of prostaglandins having one or more halogen substituent(s) at the 16 or 17 portion in high yield, in which, a dimethyl (2-oxoalkyl) phosphonate having one or more halogen substituents, a starting material, is reacted with a bicyclolactone aldehyde under the presence of an alkali metal hydride and a zinc compound.