N-alkylated 1,8-naphtho:lactam(s) prodn. - by reacting 1,8-naphtho:lactam with an aryl or alkyl sulphonic acid alkyl ester under alkaline conditions in the melt

摘要

N-alkylated 1,8-naphtholactams of formula (I) in which R = opt. substd. (cyclo)alkyl gp. and the rings (A) and (B) may contain non-ionic substituents, are prepd. by reacting a 1,8-naphtholactam cpd. of formula (II) with an alkylating agent of formula R-X (III) in which X = the residue of an aryl or alkylsulphonic acid ester, under alkaline conditions in the melt at 120-180 deg. C. The non-ionic substituents in rings (A) and (B) are e.g. halogen, alkyl, alkoxy, carboxyl, carbalkoxy, carbonamido, sulphonamide, amino, alkylamino, nitro or cyano, and esp. halogen, 1-4 C alkyl, 1-4 C alkoxy, carboxyl, -COOR1, -CON(R2)(R3), -SO2N(R2)(R3), -NH2, -NHCOR4, nitro or cyano in which R1 = opt. substd. alkyl or aryl, R2 and R3 independently = 1-4 C alkyl or opt. substd. phenyl or R2 and R3 together with the N atom may complete a satd. 5-7 membered ring which may contain additional hetero atoms, and R4 = 1-4 C alkyl or phenyl. The alkylating agent (III) is pref. a cpd. of formula (IV) in which R7 = H, halogen, opt. substd. 1-4C alkyl, 1-4C alkoxy or nitro, esp. Cl, Me or NO2 and R is as above, esp. = 1-20 C alkyl. Pref. the reaction is carried out at 140-160 deg. C in the presence of alkali metal hydroxides or alkali metal carbonates. USE/ADVANTAGE - The process gives high yields of (I) and is an improvement over prior art processes such as direct alkylation e.g. with dimethylsulphate in DMF (DE2724443) or use of an alkylating agent in a two phase system in the presence of a phase transfer catalyst (DE3445252). Prods. (I) are useful intermediates, e.g. in the prodn. of dyestuffs.