Hydrochloric Acid → (R)-1-[3-(2-Pyrrolidinyl)-2-propynyl] pyrrolidine, dihydrochloride

Participants

Reaction Conditions

Reaction Steps

A mixture of 7.0 g of (R)-2-[3-(1-pyrrolidinyl)-1-propynyl]-1-pyrrolidinecarboxylic acid, 1,1-dimethylethyl ester, 61 ml of ethanol and 61 ml of 2N hydrochloric acid is heated at 80° C. for one hour. The reaction is concentrated in vacuo and the residue is extracted with methylene chloride. The aqueous layer is concentrated in vacuo, made basic with 10N sodium hydroxide and extracted with methylene chloride. The methylene chloride solution is dried over sodium sulfate, filtered and concentrated in vacuo. The residue is dissolved in methanol, treated with an excess of methanolic hydrogen chloride and precipitated with the addition of diethyl ether. The dihydrochloride is recrystallized from hot methanol to give pure product, mp 198°-200° C. with decomposition, [α]D26° =+21°±1 (C=1.012%, methanol).

Provenance & Evidence