Mesoxalic acid → 8-Benzyl-8-azabicyclo(3.2.1)octan-3-one

Participants

Reaction Steps

A solution of 2,5-dimethoxytetrahydrofuran (50 g, 378 mmol) in hydrochloric acid (0.025 N, 160 ml) was cooled to 0° C. for 16 hours. Benzylamine hydrochloride (65 g, 453 mmol), ketomalonic acid (55 g, 377 mmol) and an aqueous solution of sodium acetate (300 ml, 0.69 M) were added and the reaction stirred at room temperature for one hour. The mixture was heated to 50° C. for further 90 minutes, then cooled in an ice bath and basified to pH12 with 2N sodium hydroxide solution. The layers were separated and the aqueous phase extracted with ethyl acetate (3×300 ml). The combined organic extracts were washed with water, dried (MgSO4), filtered and evaporated under reduced pressure. The residual brown oil was distilled under reduced pressure (126°/3 mmHg) to afford the title compound as an off-white solid (37.81 g).

Provenance & Evidence