2-Amino-5-fluoro-N-methoxy-N-methylbenzamide → (2-Amino-5-fluorophenyl)(pyridin-2-yl)methanone

Participants

Reaction Steps

To a −78° C. solution of 2-amino-5-fluoro-N-methoxy-N-methylbenzamide (9.40 g, 47.4 mmol) in THF (39.5 mL) was added isopropylmagnesium chloride 2.0M in THF (47.4 mL, 94.8 mmol) at −40° C. The solution was allowed to rise to −10° C. over 40 min then was lowered back to −40° C. in an acetonitrile/dry ice bath. To the cooled mixture was added 2-pyridylmagnesium bromide, 0.25M in THF (209 mL, 52.2 mmol) and the mixture was allowed to warm to rt. After 22 h, the reaction was diluted with DCM (200 mL) and quenched with satd ammonium chloride solution (200 mL). The aq layer was extracted with DCM (2×100 mL). The organic extract was dried over Na2SO4. The solution was filtered and concentrated in vacuo. The crude material was purified by silica gel column chromatography eluting with a gradient of 0% to 100% EtOAc in hexane, to provide (2-amino-5-fluorophenyl)(pyridin-2-yl)methanone as orange solid: 1H NMR (400 MHz, DMSO-d6) δ ppm 8.65-8.72 (1H, m), 8.02 (1H, td, J=7.7, 1.8 Hz), 7.79 (1H, dt, J=7.8, 1.0 Hz), 7.60 (1H, ddd, J=7.6, 4.9, 1.2 Hz), 7.29-7.36 (1H, m), 7.18-7.29 (3H, m), 6.88 (1H, dd, J=9.2, 4.7 Hz); LC-MS (ESI) m/z 217.0 [M+H]+.

Provenance & Evidence