Water → 4-(Bromomethyl)phenylboronic acid

A mixture of 4-methylphenylboronic acid (27.2 g; 0.2 mole) in methyl chloroform (250 ml) was heated at reflux with azeotropic removal of water until approximately 2.5 ml of water was collected and a crystalline slurry was formed. A solution of azo(bisisobutyronitrile) (1.0 g) and bromine (32 g) in methyl chloroform (25 ml) was added to the refluxing slurry over 2-3 hours. The mixture was then refluxed until the bromine colour was discharged. The reaction mixture was allowed to cool and stirred at 10°-15° C. for 30 minutes. The suspended solid was collected by filtration, washed with methyl chloroform (2×50 ml) and dried at ambient temperature to give the anhydride of 4-bromomethylphenylboronic acid (29 g) (Compound A) as a white, crystalline solid.

1. temperaturewas heated
2. customwas collected
3. customa crystalline slurry was formed
4. temperatureto cool
5. filtrationThe suspended solid was collected by filtration
6. washwashed with methyl chloroform (2×50 ml)
7. customdried at ambient temperature

ORD-Eintrag

ord-b2590efa2e9e45318afc6a859630a380

Quelldatensatz

uspto-grants-1993_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05245035