Ammonium Chloride → ethyl N-(4-propoxyphenylmethyl)piperidin-4-ylcarboxylate

Temperature

40 °C

To a stirred solution of 47.5 grams (0.30 mole) of ethyl piperidin-4-ylcarboxylate in 70 mL (0.40 mole) of N, N-diisopropylethylamine was added dropwise a solution of 52.5 grams (0.29 mole) of 4-propoxyphenylmethyl chloride in 50 mL of dimethyl sulfoxide. The reaction caused the reaction mixture temperature to rise to about 35° C. Upon completion of the addition the reaction mixture was stirred for 30 minutes, warmed to 40° C., and then allowed to cool to ambient temperature. After this time the reaction mixture was poured into 500 mL of aqueous 10% ammonium chloride. The mixture was extracted with three 250 mL portions of diethyl ether, and the combined extracts were washed with two 250 mL portions of an aqueous solution saturated with ammonium chloride, one 250 mL portion of water, and one 250 mL portion of an aqueous solution saturated with sodium chloride. The organic layer was dried with magnesium sulfate and filtered. The filtrate was concentrated under reduced pressure, yielding 80.0 grams of ethyl N-(4-propoxyphenylmethyl)piperidin-4-ylcarboxylate. The NMR spectrum was consistent with the proposed structure.

1. customto rise to about 35° C
2. additionUpon completion of the addition the reaction mixture
3. temperatureto cool to ambient temperature
4. extractionThe mixture was extracted with three 250 mL portions of diethyl ether
5. washthe combined extracts were washed with two 250 mL portions of an aqueous solution saturated with ammonium chloride, one 250 mL portion of water, and one 250 mL portion of an aqueous solution saturated with sodium chloride
6. dry with materialThe organic layer was dried with magnesium sulfate
7. filtrationfiltered
8. concentrationThe filtrate was concentrated under reduced pressure

ORD record

ord-1727d2b6d3274f518a0e4b1c2b968341

Source dataset

uspto-grants-2001_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06184234B2