Patent ID: 6740774
Filing Date: 2004-05-25
Classification: C07C

Abstract:
A process for preparing N-acyl derivatives of the formula I, in which the substituents independently of one another have the following meanings:X is CH(OR3)2, COOR3; R1 is hydrogen, optionally substituted C1-C12-alkyl, optionally substituted aryl; R2 is hydrogen, optionally substituted C1-C12-alkyl, optionally substituted aryl; R3 is optionally substituted C1-C12-alkyl, or, when X denotes CH(OR3)2, the substituents R3 together with the oxygen atoms to which they are bonded and with the carbon atom to which the oxygen atoms are bonded form a 5- or 6-membered ring; which comprises reacting a carboxamide R1â€”CONH2 of the formula II with a glyoxal monoacetal derivative of the formula III, in the presence of a carboxylic acid R4â€”COOH of the formula IV where R4 is hydrogen or optionally substituted C1-C12-alkyl, where the substituents R1 to R3 are as defined above.