MANUFACTURE OF 4-ACETAL OF BUTENEDIAL-(1,4)

4-Acetals of butene-1,4-dial of the formula …… in which R represents an alkyl, alkenyl, cycloalkyl or aralkyl radical having 1 to 12 carbon atoms, which may contain alkoxy groups, or both R together denote an alkylene or alkenylene radical having 2 to 10 carbon atoms, which may contain alkoxy groups, and R denotes an alkyl, alkenyl or alkynyl radical having 1 to 12 carbon atoms, which may be substituted by cycloaliphatic, aromatic or heterocyclic radicals or by hydroxyl, ether, thioether, acyl, alkylamino, carboxyl or carbalkoxy groups, or denotes a substituted or unsubstituted aryl radical or an alkoxy, alkylthio or acyloxy group, are prepared by reacting glyoxal monoacetals of the formula …… with aldehydes of the formula… R -CH2-CHO III,… at temperatures up to 150 DEG C