Sodium Hydroxide → HCID 86710449, compound

Temperature

-78 °C

A 1.0 M boron tribromide solution in dichloro-methane (60 mL, 60 mmol, 3 equiv) was added drop wise over 30 minutes at −78° C. to a solution of compound 4 (5.8 g, 20 mmol, 1 equiv) in dichloromethane (60 mL). The reaction was stirred at −78° C. for 4 hours, when 1H-NMR indicated that the reaction was complete. The reaction was poured into saturated sodium bicarbonate (100 mL) and the pH adjusted to 8 with 10% sodium hydroxide. The layers were separated and the aqueous phase was extracted with dichloro-methane (3×20 mL). The combined organic layers were dried over sodium sulfate, filtered, and concentrated under reduced pressure. The residue was purified over silica gel (100 g), eluting with a gradient of 60 to 100% dichloromethane in heptanes. The product containing fractions were combined, concentrated under reduced pressure and triturated with 20% methyl tert-butyl ether in heptanes (10 mL) to give compound 5 (4.3 g, 78% yield) as a white solid.

1. customThe layers were separated
2. extractionthe aqueous phase was extracted with dichloro-methane (3×20 mL)
3. dry with materialThe combined organic layers were dried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure
6. customThe residue was purified over silica gel (100 g)
7. washeluting with a gradient of 60 to 100% dichloromethane in heptanes
8. additionThe product containing fractions
9. concentrationconcentrated under reduced pressure
10. customtriturated with 20% methyl tert-butyl ether in heptanes (10 mL)

ORD record

ord-b75947ce7fc4429fb99e8092354d48f9

Source dataset

uspto-grants-2015_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09120879B2