Di:amino-cyano-pyridine cpds. prodn. - by reacting di:chloro-cyano-pyridine cpds. with prim. aliphatic amine in diluent and reacting prod. with aniline cpd. in the melt

摘要

Diaminopyridine cpds. are of formula (I), in which one of X1 and X2 = H, 1-4C alkyl, halogen or nitro and the other = CN; R1 = H, 1-4C alkyl or phenyl; R2 and R3 (same or different) = H, 1-4C alkyl or 1-4C alkoxy; R4 = H or 1-4C alkyl and R5 = 1-10C alyl (which may be interrupted by 1-3 ethercal O atoms and is opt. substd. by OH, 1-4C alkanoyloxy, phenoxy, phenyl, tetrahydrofuranyl or tetrahydropyranyl), 3-4C alkenyl or 5-7C cycloalkyl, are prepd. by reacting dichloropyridines of formula (II) in a first step with an amine of formula (III) R5-NH2 (III) at a temp. of 10-80 deg.C in the presence of a base and an inert organic diluent and/or water, and subsequently removing the diluent, then, opt. after intermediate isolation of the reaction prod., reacting this in a second step with an aniline cpd. of formula (IV) in the melt at 90-165 deg.C in weakly acid medium. USE/ADVANTAGE - The process is simple to carry out and gives high yields of the (I) of high purity, esp. high isomer purity. (I) are useful intermediates, esp. as coupling components in the synthesis of dyestuffs.