Hydrochloric Acid → HCID 131734544, compound

Participants

Reaction Conditions

Reaction Steps

Into a 100 mL eggplant-shaped flask were added benzyl 3-(2-methoxyacetyl)-2-oxopyrrolidine-1-carboxylate potassium salt (4.94 g) [mw. 329.39, 15.0 mmol], 1 mol/L hydrochloric acid (25 mL) [25 mmol] and toluene (50 mL), and the mixture was stirred for 20 min. After partitioning, the organic layer was dried over magnesium sulfate. After filtration, to the mother liquor were added cyclohexane (30 mL), p-toluenesulfonic acid monohydrate (29.0 mg) [mw. 190.22, 0.15 mmol] and p-methoxyaniline (1.85 g) [mw. 123.15, 15.0 mmol]. Dean-Stark trap was set, and the mixture was subjected to dehydration reflux for 30 min. After cooling to 25° C., 5 w/w % aqueous sodium bicarbonate solution (25 mL) was added to allow for partitioning. The organic layer was washed with 5 w/w % aqueous acetic acid solution (25 mL), further washed with 5 w/w % aqueous sodium bicarbonate solution (25 mL), dried over magnesium sulfate, filtered, concentrated under reduced pressure and purified by basic silica gel column chromatography (silica gel amount: 100 g, eluent:toluene, Rf=0.2). The effective section was concentrated under reduced pressure. Yellow candy-like product, 3.63 g, yield 61.0%, 1H-NMR (500 MHz, CDCl3, TMS) δ2.74-2.77 (m, 2H), 3.29 (s, 3H), 3.75-3.80 (m, 5H), 3.95 (s, 2H), 5.28 (s, 2H), 6.83 (d, J=8.8 Hz, 2H), 7.04 (d, J=8.8 Hz, 2H), 7.25-7.38 (m, 3H), 7.43 (d, J=7.2 Hz, 2H), 10.41 (s, 1H).

Provenance & Evidence