摘要 |
New process for the synthesis of optically active aminoacids of formula <CHEM> wherein R and R1, equal or different,represent a hydrogen atom or an alkyl radical, straight or branched, containing from 1 to 6 carbon atoms, by reacting compounds of formula <CHEM> wherein R and R1 have the above seen meanings, R2 represent a nitrile group or a COR4 group wherein R4 represents hydroxy or halogen or alkoxy, straight or branched,containing from 1 to 6 carbon atoms,or a OCOR5 wherein R5 represents an alkyl or an alkoxy group, straight or branched, containing from 1 to 6 carbon atoms and R3 represents hydrogen, an alkyl or an alkoxy radical, straight or branched, containing from 1 to 6 carbon atoms or an aryl or aralkyl radical, with an optically active alcohol of formula R6-OH (III) d or l wherein R6 represents an alkyl or cycloalkyl group, substituted or unsubstituted, containing from 3 to 12 carbon atoms, to obtain a pair of diastereoisomer esters of formula <CHEM> which is resolved in basic medium into the single diastereoisomer esters of formula <CHEM> from which the desired optically active aminoacid of formula (I) is obtained by treatment in acid medium. |