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

Participants

Reaction Steps

2.4 Grams of 1-methyl-5-(2,3-epoxypropoxy)-3,4-dihydrocarbostyril and 2.0 g of 4-benzylpiperidine were mixed with 30 ml of methanol and the mixture was heated under refluxing condition for 3 hours. The reaction mixture was concentrated under a reduced pressure and the residue thus obtained was dissolved in 30 ml of acetone and a 5%-oxalic acid-acetone solution was added under stirring at a room temperature to adjust the pH to 4.5 and allowed to stand. The precipitates thus formed were collected by filtration, washed with acetone and recrystallized from ethanol-ether to obtain 3.9 g (yield: 78%) of 1-methyl-5-[2-hydroxy-3-(4-benzyl-1-piperidyl)propoxy]-3,4-dihydrocarbostyril monooxalate as in the form of colorless powder. Melting point: 150°-152° C.

Provenance & Evidence