Pyridine → phenyl(1H-pyrrolo[2,3-c]pyridin-2-yl)methanone O-benzyloxime hydrochloride

Participants

Reaction Conditions

Reaction Steps

A mixture of phenyl[1-(phenylsulfonyl)-1H-pyrrolo[2,3-c]pyridin-2-yl]methanone (Reference Example 13) (200 mg, 0.55 mmol), O-benzylhydroxylamine hydrochloride (97 mg, 0.92 mmol) and pyridine (74 μL, 0.92 mmol) in 1,2-dichloroethane (8 mL) was heated at 60° C. After 24 h, saturated NH4Cl (10 mL) was added and the mixture was extracted with EtOAc (2×25 mL). The combined extracts were washed with saturated NaCl (20 mL), dried (Na2SO4) and concentrated under reduced pressure. Purification by column chromatography (silica gel, 1:1 hexanes/EtOAc) gave phenyl(1H-pyrrolo[2,3-c]pyridin-2-yl)methanone O-benzyloxime hydrochloride (84 mg, 47%) as a mixture of isomers: mp 153-155° C.; 1H NMR (500 MHz, DMSO-d6) δ 5.35-5.40 (2H, m), 6.66 (0.5H, s), 7.12 (0.5H, s), 7.34-7.56 (10H, m), 8.07 (0.5H, d, J=6.3 Hz), 8.19 (0.5H, d, J=6.3 Hz), 8.29 (0.5H, d, J=6.3 Hz), 8.34 (0.5H, d, J=6.3 Hz), 8.99 (0.5H, s), 9.17 (0.5H, s), 13.04 (0.5H, s), 13.14 (0.5H, s), 15.14 (1H, br s); ESI MS m/z 328 [C21H17N3O+H]+; HPLC (Method A) 98.3% (AUC), tR=19.1 and 19.3 min.

Provenance & Evidence