Vinylene carbonate → 2-(1-(3,5-Dichloropyridin-4-yl)piperidin-4-yl)oxazole

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-(3,5-dichloropyridin-4-yl)piperidine-4-carboxamide 23 (0.10 g, 0.36 mmol) in polyphosphoric acid (5 mL) at 80° C. was added vinylene carbonate (35 mg, 0.40 mmol). The mixture was heated at 170° C. for 4 hours, cooled to r.t. and poured into water (200 mL). The mixture was extracted with ethyl acetate (3×50 mL) and the combined organic extracts were washed with water (100 mL), a saturated solution of sodium hydrogen carbonate (50 mL), water (50 mL), brine (50 mL), dried (MgSO4) and concentrated under reduced pressure to furnish a colourless oil (12 mg). The crude product was purified by preparative tlc on silica gel (CH2Cl2, MeOH, 10:1 then hexane, EtOAc, 1:1) to furnish the title compound as a white solid (13 mg, 12%), LC-MS (ESI) Rt 2.66 min, m/z 298 (100%, W); m/z (ESI) C13H14Cl2N3O requires 298.0508 found [M+H]+ 298.0507.

Provenance & Evidence