Diastereo- and enantio-selective synthesis of dihydro- and tetrahydro-pyrimidines. A new strategy for the asymmetric synthesis of β-amino ketones and γ-amino alcohols

Abstract

Chiral 1,2-dihydro-(3) and 1,2,3,6-tetrahydro-pyrimidines (4) have been synthesized by reaction of 3-aminoalk-2-enimines (1) with chiral aldehydes, the structure of (4) being confirmed by an X-ray crystal structure determination of a reduction product; a new strategy for the asymmetric synthesis of β-amino ketones (2) and γ-amino alcohols (6) with two or three chiral centres is described.