Ethylene Glycol → HCID 57837478, compound

Participants

Reaction Steps

Cyclopropyl(2-cyclopropylpyrazolo[1,5-a]pyridin-3-yl)methanone (1.0 g, 4.42 mmol) was heated in benzene (80 ml) to reflux in a Dean-Stark apparatus, in the presence of TsOH monohydrate (0.8 g, 4.21 mmol, 0.95 eq.), for 10 minutes. Freshly distilled ethylene glycol (2.0 g, 32.24 mmol, 7.3 eq.) was added and the biphasic solution maintained at reflux for a further 12 hours. The reaction was cooled to rt and extracted with a saturated NaHCO3 solution (25 ml×3). The organic phase was dried over Na2SO4, filtered and concentrated in-vacuo. Purification by column chromatography (4:1 hexane:ethyl acetate) provided 2-cyclopropylpyrazolo[1,5-a]pyridine as a faintly yellow oil (0.61 g, 3.85 mmol, 87%).

Provenance & Evidence