Amino Acids, I
Syntheses of Amino Acids from Halocarboxylic Alkyl Esters and Alkali Metal Cyanates')a-and w-halo-as well as a,wdihalocarboxylic alkyl esters react with potassium cyanate in the presence of alcohol at 80-120°C in dipolar aprotic solvents to yield a-and o-(alkoxycarbonylamino)-and a,w-bis(alkoxycarbony1amino)carboxylic alkyl esters, respectively, in good yields. Hydrolytic cleavage of these mono-or diurethanes with an aqueous solution of hydrochloric acid/formic acid leads to the corresponding amino acid hydrochlorides in nearly quantitative yields.