Triphenylphosphine → (S)-4-Benzyl-3-[(2S)-3-(4-{2-[2-(4-chloro-phenyl)-5-methyl-oxazol-4-yl]-ethoxy}-2-methyl-phenyl)-2-ethoxy-propionyl]-oxazolidin-2-one

Participants

Reaction Steps

To a ice cold solution of (S)-4-benzyl-3-[(2S)-2-ethoxy-3-(4-hydroxy-2-methyl-phenyl)-propionyl]-oxazolidin-2-one (100 mg, 260 μmol), 2-[2-(4-chloro-phenyl)-5-methyl-oxazol-4-yl]-ethanol (93 mg, 390 μmol) (prepared from methyl 3-oxopentanoate and 4-chloro-benzamide in analogy to the sequence described for the synthesis of 2-(5-methyl-2-phenyl-oxazol-4-yl)-ethanol in M. Scalone, PCT WO 01/79202 A1) and triphenylphosphine (103 mg, 390 mmol) in tetrahydrofuran (2.5 ml) was added diethyl azodicarboxylate (61 μl, 390 μmol). The cooling bath was removed and stirring was continued for 12 h. Evaporation of the solvent under reduced pressure gave a yellow oil which was purified by column chromatography (silica gel, cyclohexane/AcOEt) to give 70 mg (120 μmol, 45%) of the title compound as colorless oil.

Provenance & Evidence