Hydrochloric Acid → 1-(Pyridin-2-yl)piperazin-2-one

Participants

Reaction Conditions

Reaction Steps

A stirred suspension of 2-(2-hydroxyethylamino)-N-pyridin-2-yl-acetamide (0.17 g, 0.87 mmol) under an inert atmosphere in THF (3 mL) was cooled to 0–5° C. Tributyl phosphine (0.32 mL, 1.15 mmol) was added followed by a solution of di-tert-butylazodicarboxylate (0.29 g, 1.23 mmol) in THF (3 mL) dropwise over 15 min. After a further 15 min. the mixture was warmed to 40° C. and a hydrogen chloride solution in diethylether (1M, 1.8 mL) added to produce a precipitate. The mixture was cooled to 0–5° C. and the solids filtered off to give a hydroscopic product. This was dissolved in MeOH—NH3 and chromatographed on silica gel, eluting with DCM:MeOH (100:0 to 90:10), to afford the title compound (100 mg, 65%) as a colourless solid. 1H NMR (360 MHz, d6-DMSO) δ 2.85 (1H, br s), 3.01 (2H, t, J=5.5 Hz), 3.44 (2H, s), 3.82 (2H, t, J=5.5 Hz), 7.17–7.22 (1H, m), 7.75–7.86 (2H, m), 8.41–8.45 (1H, m). MS (ES+) 178 (M+1).

Provenance & Evidence