Method of preparing a heterocyclic intermediate for the production of optically active aryloxysubstituted vicinal aminoalcohols.

摘要

The invention relates to a method of preparing a heterocyclic intermediate of the general formula wherein X is a carbonyl group, a thiocarbonyl group, a (C1-C10)(ar)alkylidene group or a dihydrocarbylsilyl group, R is a straight or branched (C1-C10)alkyl group, optionally substituted with halogen, hydroxy, (C1-C4)alkoxy or protected hydroxy, or a phenyl(C1-C3)alkyl or heteroaryl(C1-C3)alkyl group, which groups are optionally substituted with 1-3 substituents, selected from the group consisting of hydroxy, (C5-C12)cycloalkyl, amino, nitro, halogen, cyano, alkoxy, alkylcarbonyloxy, alkylcarbonylamino, alkylsulphonylamino, alkylsulphonyl, alkylcarbonyl, and alkyl, wherein the alkyl groups have 1-5 carbon atoms, and which intermediate has either the R or the S configuration, by subjecting an optically active cyanohydrin of the general formula to a reduction-transimination-reduction sequence, using R - NH2 as the primary amine, followed by a cyclization reaction and, finally, by an ozonolysis-reduction sequence.