Carbonochloridic acid, 4-methoxyphenyl ester → 4-(1-Ethylpropyl)piperazine-1-carboxylic acid 4-methoxyphenyl ester

To a stirred mixture of 1-(1-ethylpropyl)piperazine (156 mg, 1.0 mmol) and dry DCM (10 ml) was added 4-methoxyphenyl chloroformate (190 mg, 1.0 mmol). The mixture was stirred overnight at room temperature and then diluted with DCM (50 ml). The reaction mixture was washed with 1 N NaOH (3×20 ml) and water (3×20 ml) and dried (MgSO4). The organic solution was concentrated to yield an oil that was dissolved in a 0.5 N HCl solution (30 ml). The acidic solution was washed with diethyl ether (2×20 ml) and 4 N NaOH was added until pH 11. The resulting mixture was extracted with ethyl acetate (2×20 ml) and the combined organic extracts were dried (MgSO4). The solvent was evaporated to give an oil that crystallized on standing. This afforded 185 mg (60%) of the title compound as a solid. M.p. 52–54° C.

1. washThe reaction mixture was washed with 1 N NaOH (3×20 ml) and water (3×20 ml)
2. dry with materialdried (MgSO4)
3. concentrationThe organic solution was concentrated
4. customto yield an oil that
5. washThe acidic solution was washed with diethyl ether (2×20 ml) and 4 N NaOH
6. additionwas added until pH 11
7. extractionThe resulting mixture was extracted with ethyl acetate (2×20 ml)
8. dry with materialthe combined organic extracts were dried (MgSO4)
9. customThe solvent was evaporated
10. customto give an oil that
11. customcrystallized

ORD record

ord-5884c210a50e4b888feaa258622af18c

Source dataset

uspto-grants-2007_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07208497B2