Lithium hydroxide, monohydrate → 5-([Butyl(methyl)amino]methyl)thiophene-2-carboxylic acid

To a solution of methyl 5-{[butyl(methyl)amino]methyl}thiophene-2-carboxylate (280 mg, 1.16 mmol) in 2:1:1 dioxane/methanol/water (8.0 mL) is added lithium hydroxide monohydrate (146 mg, 3.38 mmol) and the reaction mixture stirred at room temperature overnight. The reaction mixture is concentrated under reduced pressure and the solid residue partitioned between ethyl acetate and water The aqueous phase is acidified to pH 1 with 1 N hydrochloric acid and extracted several times with 3:1 chloroform/2-propanol. The combined organic phase is washed with water, and brine, dried (sodium sulfate), filtered, and concentrated under reduced pressure to provide the title compound in pure form. 1H NMR (300 MHz, CD3OD) δ 7.75 (d, J=4 Hz, 1H), 7.41 (d, J=4 Hz, 1H), 4.63 (s, 2H), 3.20–3.14 (m, 2H), 2.85 (s, 3H), 1.82–1.72 (m, 2H), 1.42 (tq, J=8, 7 Hz, 2H), 0.99 (t, J=7 Hz, 3H).

1. concentrationThe reaction mixture is concentrated under reduced pressure
2. customthe solid residue partitioned between ethyl acetate and water The aqueous phase
3. extractionextracted several times with 3:1 chloroform/2-propanol
4. washThe combined organic phase is washed with water, and brine
5. dry with materialdried (sodium sulfate)
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure

ORDレコード

ord-6d81c73ba8b9472c99cfbf32a12f1b4a

出典データセット

uspto-grants-2007_02

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US07176242B2