Triisopropyl borate → 3-Benzyloxy-phenylboronic acid

A solution of 3-benzyloxy-bromobenzene 10 g (38 mmol) in 150 mL of anhydrous THF was cooled to -70° C. under a nitrogen atmosphere. 28.5 mL of n-butyl lithium (1.6M in hexanes) was added dropwise to the solution. The reaction mixture was stirred for 30 minutes, then tri-isopropyl borate 10.6 mL (45.6 mmol) was added. The reaction mixture was allowed to warm to ambient temperature over a two hour period. The reaction was quenched by the addition of 200 mL of 1N HCl and the reaction mixture was stirred for an additional hour. The slurry was extracted twice with EtOAc and the organic layer separated and combined. The EtOAc solution was washed twice with brine, dried with Na2SO4, and evaporated to a yellow oil. The product was crystallized from ether-hexane. This yielded 4.85 g of the title compound as white solid.

1. customThe reaction was quenched by the addition of 200 mL of 1N HCl
2. stirringthe reaction mixture was stirred for an additional hour
3. extractionThe slurry was extracted twice with EtOAc
4. customthe organic layer separated
5. washThe EtOAc solution was washed twice with brine
6. dry with materialdried with Na2SO4
7. customevaporated to a yellow oil
8. customThe product was crystallized from ether-hexane

ORD record

ord-1e352e05afd1446a950bf6d7c13470a6

Source dataset

uspto-grants-1998_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05843940