DE2918486

The invention relates to a process for the preparation of N-substituted acrylamides of the general formula (I) wherein Y denotes a bivalent straight - or branched chain radical with 2 to 30, preferably 2 to 18, and particularly 2 to 6 carbon atom-, preferably a group of the formula (Y1)m-(Y2)n-(Y3)t, in which Y1, Y2 and Y3 each stands for an alkylene group or the radical of a cyclic organic ring system with 5 or 6 carbon atoms, and the sum of m, n, and t is 2 or 3, and R1 denotes hydrogen or the radical of an amine of the formula N(R2) (R3), wherein R2 and R3 stand for alkyl radicals with 1 to 4 carbon atoms, which method is characterized in that dihydracrylic acid amide of the general formula (II) is transmitted with amines of the general formula H2N-(Y)-R1 (III) with elimination of ammonia and the resulting N-substituted beta -carboxylic acid amides are converted into the desired N-substituted acrylamides at elevated temperatures by splitting out of water. The conversion of the N-substituted acrylamides with splitting out of water is preferably effected in the presence of a catalyst. The splitting out of water is preferably carried out at a temperature of 100 DEG to 200 DEG C. The second stage (splitting out of water) follows batch-wise at 70 DEG to 200 DEG C. or continuously at 250 DEG to 450 DEG C.