Cesium carbonate → 1-(6-(trifluoromethyl)pyridin-3-yl)-1H-pyrazole-3-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

A mixture of 1H-pyrazole-3-carbaldehyde (0.700 g, 7.29 mmol), 5-bromo-2-(trifluoromethyl)pyridine (2.31 g, 10.2 mmol, 1.4 equiv), cesium carbonate (4.75 g, 14.6 mmol, 2.0 equiv), copper(I) iodide (0.069 g, 0.36 mmol, 0.05 equiv), and (1R,2R)—N1,N2-dimethylcyclohexane-1,2-diamine (0.23 mL, 1.46 mmol, 0.2 equiv) in DMF (9.5 mL) was heated in a sealed reaction vessel at 110° C. for 16 hours. The reaction was then cooled to room temperature and saturated aqueous ammonium chloride (100 mL) was added. The mixture was extracted with ethyl acetate (3×50 mL). The combined organic extracts were washed with saturated aqueous sodium chloride (50 mL), dried (Na2SO4), filtered, and concentrated in vacuo. Silica gel column chromatography (EtOAc/heptane) provided 1-(6-(trifluoromethyl)pyridin-3-yl)-1H-pyrazole-3-carbaldehyde (0.470 g, brown solid) in 27% yield. 1H NMR (400 MHz, CDCl3) δ 10.13 (s, 1H), 9.18 (d, J=2.1 Hz, 1H), 8.34 (dd, J=8.7, 2.0 Hz, 1H), 8.12 (m, 1H), 7.88 (d, J=8.5 Hz, 1H), 7.10 (d, J=1.8 Hz, 1H). MS m/z 241.9 (M+H)+; Rt-0.78 min.

Provenance & Evidence