(3S,4R)-3-[(1,3-Benzodioxol-5-yloxy)methyl]-1-benzyl-4-(4-fluorophenyl)piperidine → Paroxetine

Participants

Reaction Steps

A solution containing 8.4 g (0.02 mol) of (−)trans-1-benzyl-4-(4-fluorophenyl)-3-(3,4-methylenedioxyphenoxymethyl)piperidine in 120 ml of ethanol is hydrogenated in an autoclave in the presence of 0.6 g of 10% palladium-on-carbon catalyst at 30 to 40° C. under 2×105 Pa pressure for 2 to 3 hours. After taking up the hydrogen, the catalyst is filtered under nitrogen gas and the filtrate is evaporated to solvent-free to give 6.5 g of paroxetine base as evaporation residue in the form of a colourless oil. The product is suspended in 80 ml of water and after adding 2 ml of glacial acetic acid, it is stirred until dissolution. Then, the solution of 2 g of ammonium chloride in 10 ml of water is added to the mixture. After stirring for 4 hours, the precipitated crystalline title product is filtered at 10° C., twice washed with 10 ml of cold water each and dried on air to obtain 6,5 g (89%) of title compound, m.p.: 136-138° C.; [α]D20−86.6° (c=1, methanol).

Provenance & Evidence