METHOD OF PREPARING CYCLIC LACTAMS, PREFERABLY CAPROLACTAM Russian patent published in 2001 - IPC

FIELD: chemical industry. SUBSTANCE: cyclic lactams, more particularly caprolactam are prepared by reaction at elevated temperature in the presence of heterogeneous catalyst, water and suitable amino acid derivative of general formula I: H₂N-(CH₂)_m-COR₁ wherein R₁ is hydroxyl, O-alkyl having 1-12 carbon atoms or -N-R²R³, and R² and R⁴ are independently hydrogen, alkyl having 1-12 carbon atoms, m is integer of 3 to 12. Reaction is carried out in liquid phase using titanium dioxide as heterogeneous catalyst and organic solvent in optionally used. High yield of the final product is attained. EFFECT: more efficient preparation method. 4 cl, 3 ex, 3 tbl