PRODUCTION OF N-LONG CHAIN ACYLAMINO ACID OR ITS SALT AND PRODUCTION OF INTERMEDIATE AMIDONITRILE

PURPOSE:To easily obtain an N-long chain acylamino acid useful as a low- stimulation surfactant, etc., from an inexpensive raw material by reacting a fatty acid halide with an aminonitrile and hydrolyzing the product. CONSTITUTION:This N-long chain acylamino acid can be produced by carrying out the amldation reaction of a fatty acid halide of formula I (R CO is a 8-22C fatty acid residue; X is a halogen) with an aminonitrile of formula II (R is H or a 1-3C alkyl; R is a 1-5C alkylene) in the presence of a base (e.g. NaOH) in a solvent (e.g. water) at 0-50 deg.C, hydrolyzing the obtained amidonitrile of formula III in the presence of a base (e.g. NaOH) at 60-110 deg.C to obtain an N-long chain acylamino acid salt of formula IV (M is a cation), adjusting the pH of an aqueous solution of the compound of formula IV to 1-5 with a mineral acid and separating the acylamino acid from the solution.