Hydrochloric Acid → (2-Fluorophenyl)(1-methylpiperidin-4-yl)methanone--hydrogen chloride (1/1)

Participants

Reaction Steps

To a suspension of 7.6 g of magnesium turnings in 25 ml of tetrahydrofuran was added a few drops of ethyl bromide, with stirring under nitrogen. After the reaction began approximately 50.0 g of N-methyl-4-chloropiperidine in 125 ml of tetrahydrofuran was added dropwise at a rate such that moderate reflux was maintained. The reaction was heated under reflux for an additional hour. A solution of 37.2 g of o-fluorobenzonitrile in 30 ml of tetrahydrofuran was added dropwise. After completion of the addition the reaction mixture was heated under reflux for two hrs and stirring overnight at room temperature. The reaction mixture was poured into a solution of 85 g of ammonium chloride in 1200 ml of ice water and heated on a steam bath for 3 hrs. The mixture was cooled, extracted with benzene (3x, 250 ml) and dried over anhydrous sodium sulfate. Removal of the solvent under reduced pressure gave an oil. A 1.0 g-portion of the oil was dissolved in ether and a solution of ethereal hydrogen chloride was added. The precipitate was collected, dried and twice recrystallized from ethanol-ether to give 0.5 g (42%) of product, mp 167°-169° C.

Provenance & Evidence