Potassium Hydroxide → HCID 23312290, compound

Participants

Reaction Steps

7.8 g of 4-(naphtho[2,1-b]furan-2-yl)-1-piperidinecarboxylic acid ethyl ester is dissolved in 60 ml of ethylene glycol. After the addition of 40 ml of a 50% aqueous potassium hydroxide solution, the formed cloudy solution is heated, with vigorous stirring, for 15 hours at 160°. The reaction solution is thereupon cooled to 20° and extracted twice with 500 ml of ethyl acetate. The organic phases are washed five times with 1 liter of water each time, dried over sodium sulphate, filtered, and concentrated by evaporation. The residue is dissolved in 400 ml of 2N hydrochloric acid, and the acid solution extracted with toluene. The aqueous solution is then adjusted by addition of 10% sodium hydroxide solution to have a pH value of 12, and extracted with 1 liter of chloroform. The chloroform solution is dried with sodium sulphate, filtered, and concentrated by evaporation to obtain crude 4-(naphtho[2,1-b]furan-2-yl)-piperidine. The hydrochloride is prepared with hydrogen chloride in ethyl acetate, and recrystallised from ethyl acetate, whereupon it melts at 225°.

Provenance & Evidence