Water → HCID 612239, compound

Temperature

-78 °C

To a suspension of visnagin (920 mg, 4.0 mmol) in dichloromethane (20 mL) at −78° C. was added a solution of boron trichloride (1.0 M, 4.0 mL, 4.0 mmol) and the reaction mixture was stirred at −78° C. for 15 min then rt for 16 h. The reaction mixture was cooled to 0° C. and water (25 mL) was added slowly at first. The organics were concentrated in vacuo and the resulting suspension was diluted with 5% citric acid (150 mL) and heated at 60° C. for 1 h. The suspension was filtered, washing with water (3×50 mL) and the resulting solid was dried in a vacuum oven to afford the title compound as a yellow solid (710 mg, 83%): 1H NMR (300 MHz, CDCl3): δ 2.38 (s, 3H), 6.06 (s, 1H), 6.97 (d, J=2.2 Hz, 1H), 6.99 (s, 1H), 7.55 (d, J=2.2 Hz, 1H), 13.52 (s, 1H). MS (ES+) m/z 217.2 (M+H+).

1. waitrt for 16 h
2. temperatureThe reaction mixture was cooled to 0° C.
3. concentrationThe organics were concentrated in vacuo
4. additionthe resulting suspension was diluted with 5% citric acid (150 mL)
5. temperatureheated at 60° C. for 1 h
6. filtrationThe suspension was filtered
7. washwashing with water (3×50 mL)
8. customthe resulting solid was dried in a vacuum oven

ORD record

ord-5430ef8b6cf74da1a208f233ce3f4505

Source dataset

uspto-grants-2012_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08309545B2