Hydrochloric Acid → 4-Cyclopropylbenzeneboronic acid

Temperatur

-70 °C

2.5 M nButyllithium in hexane (14.5 mL) is added dropwise to a solution of 1-bromo-4-cyclopropyl-benzene (5.92 g) in THF (14 mL) and toluene (50 mL) chilled to −70° C. The resultant solution is stirred at −70° C. for 30 min before triisopropyl borate (8.5 mL) is added. The solution is warmed to −20° C. and then treated with 4 M aqueous hydrochloric acid (15.5 mL). The reaction mixture is further warmed to room temperature and then the organic phase is separated. The aqueous phase is extracted with ethyl acetate and the combined organic phases are dried (sodium sulphate). The solvent is evaporated and the residue is triturated with a mixture of ether and cyclohexane to give the product as a colorless solid.

1. additionis added
2. temperatureThe solution is warmed to −20° C.
3. temperatureThe reaction mixture is further warmed to room temperature
4. customthe organic phase is separated
5. extractionThe aqueous phase is extracted with ethyl acetate
6. dry with materialthe combined organic phases are dried (sodium sulphate)
7. customThe solvent is evaporated
8. customthe residue is triturated with a mixture of ether and cyclohexane

ORD-Eintrag

ord-7ac3731dc04b4cd3bf5682027ab948ca

Quelldatensatz

uspto-grants-2013_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08551957B2