Production of .beta.-amino-.alpha.,.beta.-unsaturated carboxylic acid esters

An improved process for producing a compound of the formula ##STR15## wherein A is alkyl of 1 to 12 carbon atoms, phenyl or phenyl substituted by chlorine, by alkyl of 1 to 6 carbon atoms or by alkoxy of 1 to 6 carbon atoms,

• R.sub.2 is hydrogen, alkyl of 1 to 12 carbon atoms, phenyl, phenyl substituted by chlorine, by alkyl of 1 to 6 carbon atoms or by alkoxy of 1 to 6 carbon atoms;
• cyano or the group --COOZ where Z is alkyl of 1 to 12 carbon atoms, phenyl or phenyl substituted by chlorine, by alkyl of 1 to 6 carbon atoms or by alkoxy of 1 to 6 carbon atoms, and
• R.sub.1 is phenyl or said phenyl substituted by one or two fluorine, chlorine or bromine atoms or mixtures thereof, by one, two or three methoxy or methyl groups or mixtures thereof with chlorine atoms, by cyano, by amino, by dimethylamino, by hydroxyl, by trifluoromethyl, by alkoxycarbonyl of 2 to 3 carbon atoms, by tert-butyl, by cyanophenyl, by acetyl or by alkylbenzoyloxy of 11-14 carbon atoms;
• biphenylyl;
• naphthyl or said naphthyl substituted by methoxy or by amino;
• anthryl;
• phenanthryl;
• pyrazolyl or said pyrazolyl substituted by amino;
• pyridyl or said pyridyl substituted by methyl, hydroxy or by amyloxy;
• indolyl;
• quinolyl;
• furyl or thienyl, by reacting equimolar amounts of a nitrile of formula II
• R.sub.1 CN (II)
• with an ester of formula III ##STR16## wherein X is halogen, in the presence of zinc, in an inert organic solvent at a temperature of less than 80.degree. C.,
• the improvement comprising
• hydrolyzing, the reaction product formed, in an alkaline medium;
• and
• isolating the compound of formula I.