(S)-4-Benzyl-3-(ethoxyacetyl)oxazolidin-2-one → (S)-4-benzyl-3-[(2S,3R)-3-(4-benzyloxy-2-trifluoromethyl-phenyl)-2-ethoxy-3-hydroxy-propionyl]-oxazolidin-2-one

Participants

Reaction Steps

In analogy to the procedure described in example 1 a], (S)-4-benzyl-3-ethoxyacetyl-oxazolidin-2-one (for the preparation of (S)-4-benzyl-3-ethoxyacetyl-oxazolidin-2-one see: D. Haigh, H. C. Birrell, B. C. C. Cantello, D. S. Eggleston, R. C. Haltiwanger, R. M. Hindley, A. Ramaswamy, N. C. Stevens, Tetrahedron: Asymmetry 1999, 10, 1353-1367) was reacted with 4-benzyloxy-2-trifluoromethyl-benzaldehyde in the presence of triethylamine and di-n-butylboron triflate to give (S)-4-benzyl-3-[(2S,3R)-3-(4-benzyloxy-2-trifluoromethyl-phenyl)-2-ethoxy-3-hydroxy-propionyl]-oxazolidin-2-one as colorless liquid. According to 1H-NMR spectroscopy, one of the four isomers is strongly predominating. The configuration was tentatively assigned as 2S,3R according to D. Haigh et al., Tetrahedron: Asymmetry 1999, 10, 1353-1367.

Provenance & Evidence