Acetic Acid → 1-(2-Fluorobenzyl)-1,4,5,6-tetrahydrocyclopenta[c]pyrazole-3-carboximidamide

Participants

Reaction Steps

Under a nitrogen atmosphere, 3.600 g (14.92 mmol) of 1-(2-fluorobenzyl)-1,4,5,6-tetrahydrocyclopenta[c]pyrazole-3-carbonitrile were dissolved in 37 ml of absolute methanol. 1.306 (24.17 mmol) of sodium methoxide were added and the mixture was stirred at RT for 4 h. 1.452 g (24.17 mmol) of acetic acid and 1.197 g (22.38 mmol) of ammonium chloride were added and the suspension was stirred at 50° C. overnight. The reaction mixture was concentrated and the residue was suspended in 100 ml of water and 25 ml of 1N hydrochloric acid. The mixture was extracted with dichloromethane. The aqueous phase was basified (pH=12) with 2N sodium hydroxide solution and extracted three times with a mixture of dichloromethane/methanol (v/v=8:2). The combined organic phases were dried with sodium sulphate and concentrated, toluene was added and the mixture was again concentrated to dryness. 1.94 g (50% of theory) of the target compound were obtained.

Provenance & Evidence