Methanol → HCID 13674974, compound

To a solution of 2,3-dihydro-1,4-benzodioxine-2-carboxylic acid (1.0 g, 5.6 mmol) in methylene chloride (10 mL) and methanol (10 mL) at 0° C. was added trimethylsilyidiazomethane (2 M in hexane) until yellow color persisted, and the reaction was stirred at room temperature for 15 min. The reaction mixture was concentrated to dryness and azeotroped with toluene. The residue was dissolved in anhydrous tetrahydrofuran (20 mL), and was added methyl iodide (1.8 mL, 28 mmol) and potassium hexamethyidisilazide (0.5 M in toluene, 17 mL, 8.5 mmol) at −78° C. The reaction was allowed to warm to room temperature over 4 h, diluted with ethyl acetate (100 mL), washed with saturated ammonium chloride (100 mL) and water (100 mL), dried over anhydrous sodium sulfate, filtered, and concentrated to dryness to give the title compound. 1H NMR (500 MHz, CD3OD): δ 7.07 (ddd, 1H), 6.97 (dd, 1H), 6.94 (dd, 1H), 6.85 (ddd, 1H), 5.52 (d, 1H), 4.64 (d, 1H), 3.86 (s, 3H), 3.83 (s, 3H). LC-MS: m/e 231 (M+Na)+ (2.6 min).

1. concentrationThe reaction mixture was concentrated to dryness
2. customazeotroped with toluene
3. dissolutionThe residue was dissolved in anhydrous tetrahydrofuran (20 mL)
4. temperatureto warm to room temperature over 4 h
5. washwashed with saturated ammonium chloride (100 mL) and water (100 mL)
6. dry with materialdried over anhydrous sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated to dryness

ORD record

ord-7907c82298484f3bbde308e283804726

Source dataset

uspto-grants-2009_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07576239B2