Triisopropyl borate → 4-(tert-Butyldimethylsilyloxy)phenylboronic Acid (contains varying amounts of Anhydride)

Temperature

-60 °C

To a solution of 4-tert-butyldimethylsilyloxybromobenzene (11.49 g) in tetrahydrofuran (100 ml) was added a solution of n-butyllithium in n-hexane (1.59M, 32.7 ml) dropwise at −55° C. under a nitrogen atmosphere, and the mixture was stirred for 1 hour at −60° C. To the reaction mixture was added triisopropyl borate (12.84 ml), and the mixture was stirred at −60° C. for 1 hour. The reaction mixture was warmed to ambient temperature, poured into a saturated aqueous ammonium chloride solution and extracted with ethyl acetate. The separated organic layer was washed with brine, dried over magnesium sulfate and evaporated under reduced pressure. The solid was triturated with n-hexane, filtered and washed with n-hexane to give 4-tert-butyldimethylsilyloxyphenylboronic acid (7.45 g).

1. stirringthe mixture was stirred at −60° C. for 1 hour
2. temperatureThe reaction mixture was warmed to ambient temperature
3. extractionextracted with ethyl acetate
4. washThe separated organic layer was washed with brine
5. dry with materialdried over magnesium sulfate
6. customevaporated under reduced pressure
7. customThe solid was triturated with n-hexane
8. filtrationfiltered
9. washwashed with n-hexane

ORD record

ord-b43a5dec2ada4a9ca72c1a294b36e506

Source dataset

uspto-grants-2003_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06521643B1