Triethylamine → N-[2-(1,2,6,7-tetrahydro-8H-cyclopenta[d]furo[2,3-b]pyridin-8-ylidene)ethyl]propanamide

Participants

Reaction Steps

To a solution of 1,2,6,7-tetrahydro-8H-cyclopenta[d]furo[2,3-b]pyridin-8-ylideneacetonitrile (700 mg, 3.53 mmol) in ethanol (24 mL) were added Raney cobalt (4 g) and 2M ammonia/ethanol solution (12 mL), and the mixture was stirred at room temperature for 4 hr under a hydrogen atmosphere. The catalyst was filtered through celite, and the filtrate was evaporated under reduced pressure. The residue was dissolved in dichloromethane (35 mL), triethylamine (984 μL, 7.06 mmol) and propionyl chloride (337 μL, 3.88 mmol) were added under ice-cooling, and the mixture was stirred for 5 min. The reaction solution was diluted with saturated aqueous sodium hydrogen carbonate solution, the mixture was extracted with ethyl acetate, and the extract was washed with saturated brine. The solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (methanol/ethyl acetate=0/100→10/90) to give the title compound. The obtained title compound was used for the reaction of Example 22 without purification.

Provenance & Evidence