Sodium Hydroxide → HCID 12788504, compound

Participants

Reaction Steps

A mixture of 3.44 g of trans-1-ethoxycarbonyl-4-(4-fluorophenoxy)-3-phenylpiperidine of Example 47, 50 ml of absolute ethanol and 26 ml of 20% aqueous NaOH solution is refluxed 18 hours under a nitrogen atmosphere. The ethanol is removed in vacuo, and the aqueous residue is partitioned between water and ethyl acetate. The aqueous phase is extracted with ethyl acetate, and the combined organic extracts are washed with saturated aqueous NaCl solution, dried over anhydrous Na2SO4, and concentrated in vacuo to an oil which quickly crystallizes to a solid. The solid is triturated with hexane and filtered to afford a solid, m.p. 99°-101° C. This material is dissolved in 100 ml of ether and treated dropwise with a solution of 1.05 g of fumaric acid in a mixture of 60 ml of ether and 15 ml of absolute ethanol. The resultant solid is filtered, washed with ether and dried to afford a salt of trans-4-(4-fluorophenoxy)-3-phenylpiperidine fumarate, m.p. s. 142.5°, 143° C. dec.

Provenance & Evidence