Acetic Anhydride → HCID 68717514, compound

Participants

Reaction Steps

To a solution of pyridine (8.75 mL) was added 4-amino-5-(4-nitrophenyl)pyrrolo[2,1-f][1,2,4]triazine-6-carbaldehyde (Intermediate H, Step 2) (500 mg, 1.77 mmol) followed by hydroxylamine hydrochloride (135 mg, 1.94 mmol). The solution was stirred at rt for 1 h, acetic anhydride (0.366 mL, 3.88 mmol) was added, and the solution was heated to 80° C. for 17 h. Upon cooling to rt the reaction mixture was partially rotavapped and then diluted with EtOAc (50 mL) and H2O (50 mL). The solution was transferred to a separatory funnel, and the organic layer was isolated while the aqueous layers were back extracted with EtOAc (2×25 mL). The combined organic layers were collected, dried (Na2SO4), filtered, and concentrated to dryness to afford a brown solid. This proved to be a 1:1 ratio of the title compound and N-[6-cyano-5-(4-nitro-phenyl)-pyrrolo[2,1-f][1,2,4]triazin-4-yl]-acetamide. 1H-NMR (DMSO-d6) δ 10.67 (s, 1H), 8.96 (s, 1H), 8.62 (s, 1H), 8.57 (s, 1H), 8.40 to 8.30 (m, 4H), 8.05 (s, 1H), 7.79 to 7.68 (m, 4H), 1.74 (s, 3H); MS [M+H]+=281.2, 323.0; LCMS RT=2.48 min.

Provenance & Evidence