反应详情

温度

0 °C

Trichloroborane (1M, 82 mL, 1 eq.) in DCM was added dropwise to a solution of meta-anisidine 215a (10 g, 1 eq.) in toluene (56 mL) under nitrogen at 0-5° C. over 1 hr. After stirred for 10 min at 0° C., ACN (5.2 mL, 1.20 eq.) was added. After the reaction mixture was stirred for additional 1 hr at 0° C., aluminium(III) chloride (11.9 g, 1.1 eq.) was added at 0° C. The reaction mixture was stirred at 50° C. for 16 hrs. The reaction mixture was then cooled down to 0° C., and propan-2-ol (38 mL) was added over 10 min, followed by addition of water (110 mL) over 30 min. The reaction mixture was heated to 50° C. for 3 hrs. After cooling down to 0° C., aqueous solution of sodium hydroxide (25%) was added. The aqueous layer was extracted with toluene (100 mL). The combined organic layers were washed with NaOH (25%), brine, and dried over sodium sulfate. The solvent was removed to yield compound 201a as a yellow solid in 63% yield. 1H NMR (CDCl3, 400 MHz): δ (ppm) 2.52 (s, 3H), 3.80 (s, 3H), 6.07 (d, J=2.43, 1H), 6.23 (dd, J=2.43 and 8.98 Hz, 1H), 6.43 (br s, 2H), 7.63 (d, J=8.98 Hz).

1. stirringAfter the reaction mixture was stirred for additional 1 hr at 0° C.
2. stirringThe reaction mixture was stirred at 50° C. for 16 hrs
3. temperatureThe reaction mixture was then cooled down to 0° C.
4. temperatureThe reaction mixture was heated to 50° C. for 3 hrs
5. temperatureAfter cooling down to 0° C.
6. extractionThe aqueous layer was extracted with toluene (100 mL)
7. washThe combined organic layers were washed with NaOH (25%), brine
8. dry with materialdried over sodium sulfate
9. customThe solvent was removed