Hydrochloric Acid → 2-Methylphenyl boronic acid

Temperature

-70 °C

A solution of 2-bromotoluene (1.0 g) in dry tetrahydrofuran (50 ml) was cooled to -70° C. under an atmosphere of argon. A solution of tert-butyl lithium in pentane (1.7M, 7.6 ml) was added dropwise to the mixture whilst maintaining the temperature below -60° C. The reaction mixture was stirred at -70° C. for 0.5 hours. Trimethyl borate (0.73 ml) was added and the mixture allowed to warm to ambient temperature. The mixture was poured onto a mixture of aqueous 2M hydrochloric acid and ice, and the mixture extracted with ethyl acetate. The ethyl acetate extract was washed with brine, dried (MgSO4) and evaporated to give 2-methylphenylboronic acid as a white solid (0.48 g) which was used without further purification.

1. temperaturewhilst maintaining the temperature below -60° C
2. temperatureto warm to ambient temperature
3. extractionthe mixture extracted with ethyl acetate
4. extractionThe ethyl acetate extract
5. washwas washed with brine
6. dry with materialdried (MgSO4)
7. customevaporated

ORD record

ord-b1e1d553924a43b7966feb55315a1dce

Source dataset

uspto-grants-1999_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05866611