Sodium Sulfite → Ethyl 3-cyclopropyl-2-oxopropanoate

Participants

Reaction Steps

A solution of ethyl 2-(cyclopropylmethyl)-1,3-dithiane-2-carboxylate (20.8 g, 0.084 mol) in acetone/water (97/3, v/v; 80 mL) was added drop wise over 30 minutes to a stirred suspension of N-bromosuccinimide in acetone/water (97/3, v/v, 1220 mL) at −5° C. The reaction mixture was stirred at the same temperature for 1 hour, while the progress of the reaction was monitored by thin layer chromatography, and then a mixture of methylene chloride/hexane (1/1, v/v, 500 mL) and aqueous sodium sulphite was added. The mixture was stirred until the colour faded from the organic layer. The phases were separated and the aqueous phase was extracted with methylene chloride/hexane (3×300 mL). The combined extracts were washed with aqueous sodium sulfite, water, aqueous sodium bicarbonate, brine and dried over magnesium sulfate. The solvent was removed under reduced pressure to afford ethyl 3-cyclopropyl-2-oxopropanoate (12.3 g, 93.4%), as a light yellow oil. 1H-NMR (400 MHz, CDCl3): δ=0.13-0.21 (m, 2H), 0.54-0.65 (m, 2H), 0.97-1.10 (m, 1H), 1.38 (t, J=8 Hz, 3H), 2.72 (d, J=8 Hz, 2H), 4.33 (q, J=8 Hz, 2H).

Provenance & Evidence