NOVEL 3-COMPONENT COUPLING REACTION OF CARBODIIMIDE, METHYL HYDROGEN MALEATE, AND AN ALCOHOL OR AMINE - SYNTHESIS OF N-CARBAMOYLASPARTIC ACID-DERIVATIVES

A novel three-component coupling reaction of methyl hydrogen maleate 1 , a carbodiimide 2, and an alcohol or amine gave derivatives of N-carb amoylaspartic acid (3) in moderate to excellent yields. in the couplin g, an intramolecular Michael addition of the acylisourea 6 subsequentl y occurs to give a new intermediate. 2-iminooxazolidin-5-one 7. The ad dition of alcohol or amine to the second intermediate 7 completes the three-component coupling.