Potassium Hydroxide → 3-(2-Methoxy-ethylamino)-phthalic acid

To a stirred solution of 3-(2-methoxy-ethylamino)-phthalic acid dimethyl ester (2.24 g, 8.38 mmol) in methanol (50 ml) was added 5N potassium hydroxide (10 ml). The mixture was stirred at room temperature overnight. The solvent was evaporated in vacuo and the residue dissolved in water (50 ml). The water was washed with diethyl ether (2×75 ml). The aqueous portion was cooled in an ice bath and the pH was adjusted to 2-3 by dropwise addition of concentrated hydrochloric acid. The aqueous solution was then extracted with ethyl acetate (3×75 ml). The combined ethyl acetate extracts were washed with brine (100 ml) and dried (MgSO4). The solvent was evaporated in vacuo and the residue, which contained a mixture of diacid and monomethyl esters, was used without further purification.

1. customThe solvent was evaporated in vacuo
2. dissolutionthe residue dissolved in water (50 ml)
3. washThe water was washed with diethyl ether (2×75 ml)
4. temperatureThe aqueous portion was cooled in an ice bath
5. additionthe pH was adjusted to 2-3 by dropwise addition of concentrated hydrochloric acid
6. extractionThe aqueous solution was then extracted with ethyl acetate (3×75 ml)
7. washThe combined ethyl acetate extracts were washed with brine (100 ml)
8. dry with materialdried (MgSO4)
9. customThe solvent was evaporated in vacuo
10. additiona mixture of diacid and monomethyl esters
11. customwas used without further purification

ORD record

ord-6b35ad2be6c94c34bcffc0e639d07b9e

Source dataset

uspto-grants-2011_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08012997B2