PROCESS FOR PREPARING N,N-DIEHTYL-M-TOLUAMIDE Russian patent published in 1996 - IPC

FIELD: chemical and petrochemical industries, more particularly preparation of aromatic acid dialkylamides, in part N,N- diethyltoluamide-m-toluic acid. SUBSTANCE: N,N-diethyl- m-toluamide is prepared by catalytic amidation of m- toluic acid with diethylamine in vapor phase at 260-320 C at volumetric feed rate of raw material of hr h^-1, toluic acid to diethylamine moler ratio of 1:3-7 followed by recovery of the desired product from catalyzate by rectification. The catalyst is industrial calcium- phosphate catalyst such as calcium hydroxyapatite of general formula: Ca_10-x(HPO₄)_x(PO₄)_6-x(OH)_2-x, wherein 0 ≅ X ≅ 2.. Conversion of p-toluic acid is 89.98.0%, and selectivity of N,N-diethyltoluamide formation being 96.3-99.5%. The claimed process is carried out continuously, it is simple and ecologically pure. EFFECT: more efficient preparation process. 1 tbl