HCID 23467205, compound → HCID 23467217, compound

Participants

Reaction Steps

A solution of 11 g of hexahydro-1'-benzyl-1-phenylspiro[3H-oxazolo[3,4-a]pyridine-3,4'-piperidine] in 95 ml of methanol and 5 ml of acetic acid is mixed with 1 g of 20% palladium on carbon and subjected to hydrogen pressure of about 50 p.s.i. After the theoretical amount of hydrogen is consumed, the reaction is stopped and the filtered solution is evaporated to dryness in vacuo. The residue is dissolved in methylene dichloride and stirred with excess dilute ammonium hydroxide solution to convert the acetate salt of hexahydro-1-phenylspiro[3H-oxazolo[3,4-a]pyridine-3,4'-piperidine] to the free base. The organic layer containing the aforementioned free base is separated, washed with a saturated sodium bicarbonate solution, dried over magnesium sulfate and evaporated to dryness in vacuo. The residue is recrystallized from ethyl acetate or methanol-water to obtain the pure free base of hexahydro-1-phenylspiro[3H-oxazolo[3,4-a]pyridine-3,4'-piperidine]; mp 169°-171° C.; yield 7 g.

Provenance & Evidence