Trifluoroacetic acid → HCID 58550931, compound

Participants

Reaction Steps

To 5-methyl-2-pyrrol-1-yl-phenol (6.0 g, 33.6 mmol) in dichloromethane (75 mL) was added tert-butyl 4-oxopiperidine-1-carboxylate (6.61 g, 33.6 mmol) then trifluoroacetic acid (3.1 mL, 40.3 mmol) and the mixture was stirred at room temperature for 5.5 hours. The solvent was evaporated and the crude residue was purified by column chromatography utilizing a gradient of 0-100% dichloromethane in hexanes to yield tert-butyl 7′-methylspiro[piperidine-4,4′-pyrrolo[2,1-c][1,4]benzoxazine]-1-carboxylate (7.1 g, 59%). 1H NMR (400 MHz, CDCl3) δ 7.22 (d, J=8.1 Hz, 1H), 7.12-7.09 (m, 1H), 6.88 (s, 1H), 6.82 (d, J=8.0 Hz, 1H), 6.29 (t, J=3.2 Hz, 1H), 6.00-5.98 (m, 1H), 5.30 (s, 1H), 3.97 (s, 2H), 3.26 (t, J=12.2 Hz, 2H), 2.32 (s, 3H), 2.09-2.01 (m, 2H), 1.87 (dt, J=13.3, 4.9 Hz, 2H), 1.48 (s, 9H). ESI-MS m/z calc. 354.4. found 355.5 (M+1)+; Retention time 2.28 minutes (3 min run).

Provenance & Evidence