Dimethylformamide dimethyl acetal → (2E)-3-(dimethylamino)-1-[2-(4-fluorophenyl)-6-(trifluoromethyl)-pyrazolo[1,5-a]pyridin-3-yl]-2-propen-1-one

Participants

Reaction Steps

A mixture of 1-[2-(4-Fluorophenyl)-6-(trifluoromethyl)pyrazolo[1,5-a]pyridin-3-yl]ethanone (11.85 g), 36.77 mmol) and N,N-dimethylformamide dimethyl acetal (100 mL) was stirred at reflux for 17 hours. The mixture was cooled to room temperature and then to 0° C. The resulting orange precipitate was collected by filtration, washed with cold hexanes, and dried under vacuum to afford the title compound as an orange solid, 10.17 g (73%). 1H NMR (DMSO-d6): δ 9.44 (s, 1H), 8.22 (d, 1H, J=9.4 Hz), 7.75 (m, 2H), 7.65 (d, 1H, J=9.5 Hz), 7.56 (d, 1H, J=12.4 Hz), 7.35 (m, 2H), 5.05 (d, 1H, J=12.3 Hz), 3.04 (s, 3H), 2.56 (s, 3H). MS (+ve ion electrospray) 377 (80), (M+).

Provenance & Evidence