Trifluoroacetic acid → 2,2,2-Trifluoro-1-(8'-azaspiro[benzo[b]pyrrolo[1,2-d][1,4]oxazine-4,3'-bicyclo[3.2.1]octane]-8'-yl)ethanone

Participants

Reaction Conditions

Reaction Steps

A solution of TFA (387 μL, 5.02 mmol) in dichloroethane (18 mL) was added to 2-pyrrol-1-ylphenol (401 mg, 2.52 mmol) and (1R,5S)-8-(2,2,2-trifluoroacetyl)-8-azabicyclo[3.2.1]octan-3-one (620 mg, 2.80 mmol). The solution was heated at 70° C. overnight. The solvent was evaporated and the crude residue was purified by column chromatography (silica gel: 0-10% EtOAc in hexanes) to afford 2,2,2-trifluoro-1-(8′-azaspiro[benzo[b]pyrrolo[1,2-d][1,4]oxazine-4,3′-bicyclo[3.2.1]octane]-8′-yl)ethanone as a clear oil (469 mg, 46%). 1H NMR (400 MHz, CDCl3) δ 7.27 (d, J=7.5 Hz, 1H), 7.07-6.94 (m, 4H), 6.23 (t, J=3.2 Hz, 1H), 5.87 (d, J=3.4 Hz, 1H), 4.74 (d, J=7.4 Hz, 1H), 4.42 (s, 1H), 2.50-2.34 (m, 2H), 2.34-2.16 (m, 3H), 2.16-1.89 (m, 3H). ESI-MS m/z calc. 362.4. found 363.3 (M+1)+; Retention time: 2.07 minutes (3 min run).

Provenance & Evidence