Pinacol → HCID 66617603, compound

Temperature

-78 °C

To a solution of 5-bromo-1,2-difluoro-3-(4-methoxy-benzyloxy)-benzene (0.35 g) in tetrahydrofuran (10 ml) under nitrogen was added triisopropylborate (0.29 ml). The mixture was cooled to −78° C. and 2.5M n-butyllithium solution in hexanes was added. The reaction mixture was stirred at −40° C. for 1 hour, then warmed to 20° C. and quenched with 2M hydrochloric acid (aq) (2 ml). The reaction mixture was warmed to room temperature and stirred for 1 hour. The reaction mixture was adjusted to pH 7 using saturated sodium bicarbonate solution, then partitioned between ethyl acetate and water, dried (MgSO4) and the solvents removed in vacuo to yield a crude residue (0.31 g). A mixture of this crude residue and pinacol (0.25 g) in toluene (10 ml) were stirred under reflux overnight in a Dean-Stark apparatus. The solvents were removed in vacuo, the residue was then partitioned between ethyl acetate and water, the combined organics were washed with water then brine and dried (MgSO4), the solvents were removed in vacuo to yield 2-[3,4-difluoro-5-(4-methoxy-benzyloxy)-phenyl]-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane (0.28 g)

1. temperaturewarmed to 20° C.
2. customquenched with 2M hydrochloric acid (aq) (2 ml)
3. temperatureThe reaction mixture was warmed to room temperature
4. stirringstirred for 1 hour
5. custompartitioned between ethyl acetate and water
6. dry with materialdried (MgSO4)
7. customthe solvents removed in vacuo
8. customto yield a crude residue (0.31 g)
9. stirringwere stirred
10. temperatureunder reflux overnight in a Dean-Stark apparatus
11. customThe solvents were removed in vacuo
12. customthe residue was then partitioned between ethyl acetate and water
13. washthe combined organics were washed with water
14. dry with materialbrine and dried (MgSO4)
15. customthe solvents were removed in vacuo

ORD record

ord-07b1ca44b7c143e1a399d9836521cb22

Source dataset

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08802670B2