Water → HCID 57752826, compound

Participants

Reaction Steps

To 5,7-dichloro-6-methylpyrazolo[1,5-a]pyrimidine-3-carbaldehyde (290 mg) in toluene (40 mL) was added pyridinium p-toluenesulfonate (60 mg) and propan-1,3-diol. The mixture was then heated under reflux for 2 h, with azeotropic removal of water. The solution was cooled and evaporated under reduced pressure. The residue was chromatographed on silica gel using ethyl acetate/petroleum ether ⅔ as eluent to give the title compound (310 mg) as a white solid; 1H-NMR (400 MHz, CDCl3) d(ppm): 8.32 (1H, s, 2-H), 5.97 (1H, s, CHO2R), 4.25 (2H, br dd, OCHeq), 4.05 (2H, br t, OCHax), 2.50 (3H, s, 6-Me), 2.25 (1H, m, CCHeqHC), 1.48 (1H, br d, CCHHaxC).

Provenance & Evidence