Methanol → Benzenebutanoic acid, gamma-oxo-, methyl ester

Participants

Reaction Steps

To a 1.0 L round bottom flask was added 89 g (0.5 mol) of 3-benzoylpropionic acid and 200 mL of methanol. The solution was stirred until all of the acid had dissolved. To this solution was added approximately 2.0 mL of conc. H2SO4 and the reaction refluxed for 2.5 hours. After the reaction was determined to be complete, the methanol was removed on the rotoevaporator and to the residual oil was added ethyl acetate (˜500 mL). To the ethyl acetate layer was then added 150 mL of a saturated sodium carbonate solution. The layers were extracted and allowed to separate. The organic layer was then dried (MgSO4), filtered, and concentrated to yield methyl 3-benzoylpropionate (1) as a light yellow oil. Yield 96 g; yield 100%; >97% cp. Lit bp 172–174° C. at 10 mm Hg.; 1H NMR ppm (δ), CDCl3 7.98 (dd, 2H), 7.54 (m, 1H), 7.45 (m, 2H), 3.70 (s, 3H, OCH3), 3.32 (t, 2H), 2.76 (t, 2H). 13C NMR ppm (δ), CDCl3 198.0 (C═O), 173.3 (CO2), 136.5 (q), 133.2, 128.6, 128.0, 51.7 (OCH3), 33.3, 28.0. IR oil cm−1 2952, 1737, 1687, 1596, 1449, 1358, 1221, 1168 1001, 750, 691.

Provenance & Evidence