Sodium hydride → (1,2-dimethyl-6,7-dihydrocyclopenta[e]indazol-8(2H)-ylidene)acetonitrile

Participants

Reaction Steps

To a suspension of 60% sodium hydride (58.1 mg, 1.45 mmol) in tetrahydrofuran (4 mL) was added diethyl cyanomethylphosphonate (255 μL, 1.58 mmol), and the mixture was stirred at room temperature for 15 min. A solution of 1,2-dimethyl-6,7-dihydrocyclopenta[e]indazol-8(2H)-one (243 mg, 1.21 mmol) in tetrahydrofuran (8 mL) was added thereto, and the mixture was stirred at 60° C. for 24 hr. The reaction solution was diluted with saturated aqueous sodium hydrogen carbonate solution, extracted with ethyl acetate, washed with water and saturated brine, and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (ethyl acetate/hexane=30/70→80/20) to give the title compound (122 mg) as a mixture with 1,2-dimethyl-6,7-dihydrocyclopenta[e]indazol-8(2H)-one. The obtained title compound was used for the reaction of Reference Example 28 without purification.

Provenance & Evidence