Carbon tetrabromide → Methyl 7-(5-phenyl-1,3-oxazol-2-yl)heptanoate

Participants

Reaction Steps

Add a solution of 7-(2-oxo-2-phenylethylcarbamoyl)heptanoic acid methyl ester (7.05 g, 23.1 mmol) and carbon tetrabromide (11.3 g, 34.3 mmol) in methylene chloride over 40 minutes to a mixture of triphenylphosphine (9.0 g, 34.3 mmol) and DMAP (5.51 g, 45.1 mmol) in methylene chloride (500 mL) at room temperature under nitrogen. Stir the mixture for 30 minutes and add additional triphenylphosphine (2.6 g, 9.92 mmol) and carbon tetrabromide (3.35 g, 10.1 mmol). Stir the mixture for an additional 20 minutes, filter through Celite and wash with ethyl acetate (3×100 mL). Remove the solvent under reduced pressure and purify the residue by flash column chromatography on silica gel, eluting with hexanes/ethyl acetate (70:30), to provide 7-(5-phenyloxazol-2-yl)heptanoic acid methyl ester (2.75 g, 41%).

Provenance & Evidence