in which x is cl br f or i preferably br and y is o c 1 c 6 alkyl preferably iso propyloxy preferably the reaction is carried out by reacting a 2 halo 2 propenal 3 alkyl ether such as 2 bromo 3 1 methylethoxy 2 propenal with a n 1 iminoalkyl aminoalkylaryl compound such as n 1 iminopentyl 4 aminomethyl benzoic acid or n 1 iminopentyl 4 aminomethyl naphthoic acid in the presence of base such as an inorganic base for example sodium or potassium carbonate or sodium or potassium hydroxide preferably potassium carbonate in solvent such as water organic solvent mixture for example water and tetrahydrofuran water and acetonitrile or water and chloroform containing 1 4 7 10 13 16 hexaoxacyclooctadecane 18 crown 6 preferably water and tetrahydrofuran suitably the reaction is carried out at a temperature of between about 10 u00b0 c and about 80 u00b0 c preferably between about 25 u00b0 c and about 65 u00b0 c alternately the reaction is carried out in the presence of an organic base and in an organic solvent for example a 2 halo 2 propenal 3 alkyl ether such as 2 bromo 3 1 methylethoxy 2 propenal is reacted with a n 1 iminoalkyl aminoalkylaryl compound such as ethyl n 1 iminopentyl 4 aminomethyl benzoate or ethyl n 1 iminopentyl.