Ramón Badorrey, C. Cativiela, M. D. Díaz-de-Villegas
Mar 10, 2000
Citations
0
Influential Citations
15
Citations
Journal
Tetrahedron-asymmetry
Abstract
Abstract (2 R ,3 S )-4-Halo-3-benzyloxy-2-( N -methoxycarbonyl- N -benzylamino)butyronitriles have been prepared through an efficient three-step sequence from (2 R ,3 S )-2-benzylamino-3-benzyloxy-4-( tert -butyldimethylsilyloxy)butyronitrile, which is readily available in diastereomerically pure form by a Strecker-type reaction of the N -benzylimine, derived from selectively protected ( R )-glyceraldehyde, and trimethylsilyl cyanide. These compounds enable the facile synthesis of chiral β-hydroxy-α-amino acids containing virtually any nucleophile capable of substituting the γ-halogen atom. As an illustration of their synthetic potential, the 4-bromo derivative has been successfully converted into (1 R ,2 R )-2-benzyloxy-1-( N -methoxycarbonyl- N -benzylamino)cyclopropanecarboxamide, which is a new conformationally restricted serine analogue, in two steps: base-induced cyclisation and subsequent hydrolysis of the nitrile group.