Patent ID: 6395920
Filing Date: 2002-05-28
Classification: C07B,C07C,Y02P

Abstract:
A process for preparing 2-substituted and 2,2disubstituted acetals of malondialdehyde of general forms I: in which R1, R2, R3 and R4 are selected from the group consisting of the same or different alkyl groups, cycloalkyl groups, aralky groups or aryl groups with up to 12 carbon atoms and which R5 is a member selected from the group consisting of COOH, COONa, COOR, CHO, C(OR)2, CN, CONH2, CONHR, or CONR2, and R6 is independently, selected from the group consisting of H, alkyl, cycloallyl, aralkyl, aryl, COOH, COONa, COOR, CHO, C(OR)2, CN, CONH2, CONHR or CONR2 with the proviso that R5 and R6 cannot both=H, alkyl, cycloalkyl, aryl or aralky, which comprises reacting a compound of general formula III: with an ortho formate of general formula IV: in the presence of an acidic homogeneous or heterogeneous catalyst having a concentration of from about 0.00001 w/w-% to about 5000 w/w-% of compound III at a temperature in the range of about âˆ’100Â° C. to about 220Â° C.