Hydrochloric Acid → 4-Cyclopropylbenzeneboronic acid

Temperatur

-70 °C

2.5 M nButyllithium in hexane (14.5 mL) is added dropwise to 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 washed 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. washthe residue is washed with a mixture of ether and cyclohexane

ORD-Eintrag

ord-0ba6ce0f6e0e40739ff825ced6ba4d1c

Quelldatensatz

uspto-grants-2010_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07745414B2