Hydrochloric Acid → HCID 58461093, compound

Temperature

-78 °C

First, 5.0 g of 2,6-dibromonaphthalene was placed into a 500-mL three-neck flask, and the air in the flask was replaced with nitrogen. To this compound was added 200 mL of tetrahydrofuran (THF), and this solution was stirred at −78° C. for 20 minutes. Then, 12 mL of a 1.7M hexane solution of n-butyllithium (n-BuLi) was dripped into this mixture solution, followed by stirring at −78° C. for 2 hours. After the predetermined time had elapsed, 3.5 mL of trimethyl borate was added to the mixture and this solution was stirred for 18 hours while the temperature was raised to room temperature. After the predetermined time had elapsed, 80 mL of 1.0M hydrochloric acid was poured into this solution, and the mixture was stirred for 1 hour. Then, the mixture solution was separated into an organic layer and an aqueous layer. Organic substances were extracted with ethyl acetate from the obtained aqueous layer. The solution of the extract was combined with the organic layer that had been first obtained, and the mixture was washed with saturated brine and dried by addition of anhydrous magnesium sulfate. Then, the filtrate obtained by gravity filtration was concentrated to give a white solid. The obtained white solid was washed with ethanol, whereby 6-bromonaphthalene-2-boronic acid was obtained (as a white powder in 35% yield). The synthesis scheme of Step 1 is illustrated in the following (a-4).

1. stirringby stirring at −78° C. for 2 hours
2. stirringthis solution was stirred for 18 hours while the temperature
3. temperaturewas raised to room temperature
4. stirringthe mixture was stirred for 1 hour
5. customThen, the mixture solution was separated into an organic layer
6. extractionOrganic substances were extracted with ethyl acetate from the obtained aqueous layer
7. customhad been first obtained
8. washthe mixture was washed with saturated brine
9. dry with materialdried by addition of anhydrous magnesium sulfate
10. customThen, the filtrate obtained by gravity filtration
11. concentrationwas concentrated
12. customto give a white solid
13. washThe obtained white solid was washed with ethanol

ORD record

ord-9ff099bc6663486caf5ad55d8b5c5ebe

Source dataset

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09056883B2