4-Benzylpiperidine → 2(1h)-quinolinone, 3,4-dihydro-5-(2-hydroxy-3-(4-(phenylmethyl)-1-piperidinyl)propoxy)-1-(2-propenyl)-, ethanedioate (1:1) (salt)

Participants

Reaction Steps

2.6 Grams of 1-allyl-5-(2-hydroxy-3-chloropropoxy)-3,4-dihydrocarbostyril, 1.5 g of triethylamine and 2.0 g of 4-benzylpiperidine were mixed with 30 ml of dimethylformamide and the mixture was stirred at 80°-90° C. for 5 hours. The reaction mixture was poured into 80 ml of a 5%-sodium hydrogencarbonate aqueous solution and the organic layer was extracted with chloroform, and the chloroform layer was washed with water and dried. Then the chloroform was removed by distillation and the residue thus obtained was dissolved in 30 ml of acetone and further 5%-oxalic acid acetone solution was added to make the pH to 4.5 and the crystals formed were collected by filtration and washed with acetone. Recrystallization from ethanol to obtain 4.3 g (yield: 82%) of 1-allyl-5-[2-hydroxy-(4-benzyl-1-piperidyl)propoxy]-3,4-dihydrocarbostyril monooxalate as in the form of colorless needle-like crystals. Melting point: 178°-180° C.

Provenance & Evidence