Patent ID: 6395914
Filing Date: 2002-05-28
Classification: C07C,Y02P

Abstract:
A process for preparing acetals of malondialdehyde of general formula I: in which R1, R2, and R3 are the same or different alkyl groups, cycloalkyl groups, aralkyl groups, or aryl groups with up to 12 carbon atoms, R4 is an alkyl group, cycloalkyl group, aralkyl group, or represents R7â€”COâ€” with R7=alkyl, cycloalkyl, aralkyl, or aryl, with up to 12 carbon atoms, and R5 and R6 represent independently of each other H, an alkyl group, a cycloalkyl group, an aralkyl group or an aryl group with up to 12 carbon atoms, which process comprises reacting an alkyl vinylether of general formula II or a vinylester of general formula III: â€ƒin which R4, R5 and R6 are as defined above and R7 is an alkyl group, cycloalkyl group, aralkyl group, or aryl group with up to 12 carbon atoms, with an ortho formate of general formula IV: â€ƒin the gas phase using an acidic heterogeneous catalyst under a vacuum of from about 0.5 mm to about 500 mm Hg.