Acetic Anhydride → HCID 58550817, compound

Participants

Reaction Conditions

Reaction Steps

Acetic anhydride (4.0 mL, 42 mmol) was added to (Z)-1′-(4-ethyl-3-methoxybenzoyl)spiro[benzo[b]pyrrolo[1,2-d][1,4]oxazine-4,4′-piperidine]-1-carbaldehyde oxime (847 mg from previous step). The reaction mixture was heated at 140° C. for 3.5 h then cooled to room temperature and poured onto ice. Dichloromethane (30 mL) was added followed by sodium bicarbonate (0.7 g). The organic phase was then separated and the aqueous layer was extracted twice with dichloromethane. The combined organic layers were washed with brine, dried, filtered, and concentrated to give a yellow oil. The crude material was purified by column chromatography (silica gel: 5-45% EtOAc in hexanes) to give 1′-(4-ethyl-3-methoxybenzoyl)spiro[benzo[b]pyrrolo[1,2-d][1,4]oxazine-4,4′-piperidine]-1-carbonitrile (944 mg, 69%). 1H NMR (400 MHz, CDCl3) δ 8.10 (d, J=8.0 Hz, 1H), 7.22-7.16 (m, 1H), 7.15-7.08 (m, J=7.6 Hz, 3H), 7.00 (d, J=4.0 Hz, 1H), 6.93-6.87 (m, 2H), 6.08 (d, J=4.0 Hz, 1H), 4.64 (s, 1H), 3.83 (s, 3H), 3.65-3.14 (m, 3H), 2.62 (q, J=7.5 Hz, 2H), 2.27-1.67 (m, 4H), 1.16 (t, J=7.5 Hz, 3H). ESI-MS m/z calc. 427.5. found 428.5 (M+1)+; Retention time: 2.08 minutes (3 min run).

Provenance & Evidence