Dimethyl Sulfoxide → 3-[4-(3-Phenylpyrazolo[1,5-a]pyrimidin-6-yl)phenyl]propanal

Participants

Reaction Conditions

Reaction Steps

Dimethylsulfoxide (0.862 mL, 12.2 mmol, 5.00 equiv) was added to a solution of oxalyl chloride (0.636 mL, 7.29 mmol, 3.00 equiv) in dichloromethane (10 mL) at −78° C. The mixture was stirred for 15 minutes before a solution of 3-[4-(3-phenylpyrazolo[1,5-a]pyrimidin-6-yl)phenyl]propan-1-ol (2-4, 0.800 g, 2.43 mmol, 1 equiv) in dichloromethane (100 mL) was added via cannula over 5 minutes. The resulting mixture was stirred at −78° C. for 1 hour. Triethylamine (3.50 mL, 25.1 mmol, 10.3 equiv) was added, and the mixture was then warmed to 0° C. and stirred for 30 minutes. The reaction mixture was partitioned between saturated sodium bicarbonate solution (100 mL) and additional dichloromethane (100 mL). The organic layer was dried over sodium sulfate and concentrated to give 3-[4-(3-phenylpyrazolo[1,5-a]pyrimidin-6-yl)phenyl]propanal (2-5) as a yellow solid. 1H NMR (400 MHz, CDCl3) δ9.86 (t, 1H, J=1.2 Hz), 8.82 (d, 1H, J=2.4 Hz), 8.81 (d, 1H, J=2.4 Hz), 8.46 (s, 1H), 8.06 (br d, 2H, J=7.8 Hz), 7.54 (d, 2H, J=8.2 Hz), 7.47 (t, 2H, J=7.8 Hz), 7.37 (d, 2H, J=8.2 Hz), 7.29 (t, 1H, J=7.8 Hz), 3.05 (t, 2H, J=7.1 Hz), 2.86 (t, 2H, J=7.1 Hz).

Provenance & Evidence