Triisopropyl borate → 4-(2-Fluorophenoxy)phenylboronic acid

Temperatur

-78 °C

Into a 100 mL 3-necked round-bottom flask purged and maintained under an inert atmosphere of nitrogen, was placed a solution of 1-(2-fluorophenoxy)-4-iodobenzene (3.3 g, 10.51 mmol, 1.00 equiv) in tetrahydrofuran (50 mL). n-BuLi (4.4 mL) was added dropwise with stirring at −78° C. The resulting solution was stirred for 10 mins at −78° C. and then tris(propan-2-yl)borate (2.1 g, 11.17 mmol, 1.06 equiv) was added dropwise with stirring at −78° C. over 10 min. The resulting solution was stirred while the temperature warmed from −78° C. to room temperature. The reaction was then quenched by the addition of saturated aqueous NH4Cl and concentrated under vacuum. The resulting solution was diluted with 10% aquious potassium hydroxide and then washed with ether. The pH of the aqueous was adjusted to 2-4 with hydrogen chloride (37%). The resulting solution was extracted with ethyl acetate and the organic layers combined and dried over anhydrous sodium sulfate and concentrated under vacuum to give 2.2 g (90%) of [4-(2-fluorophenoxy)phenyl]boronic acid as a white solid

1. customInto a 100 mL 3-necked round-bottom flask purged
2. temperaturemaintained under an inert atmosphere of nitrogen
3. stirringThe resulting solution was stirred for 10 mins at −78° C.
4. stirringwith stirring at −78° C. over 10 min
5. stirringThe resulting solution was stirred while the temperature
6. temperaturewarmed from −78° C. to room temperature
7. customThe reaction was then quenched by the addition of saturated aqueous NH4Cl
8. concentrationconcentrated under vacuum
9. additionThe resulting solution was diluted with 10% aquious potassium hydroxide
10. washwashed with ether
11. extractionThe resulting solution was extracted with ethyl acetate
12. dry with materialdried over anhydrous sodium sulfate
13. concentrationconcentrated under vacuum

ORD-Eintrag

ord-af7147e613ad45f2b5d138da4ccfefe5

Quelldatensatz

uspto-grants-2014_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08759358B1