Triisopropyl borate → HCID 57468822, compound

Temperature

20 °C

Step 2) To a solution of the above prepared 4-bromo-2-(2,5-dimethyl-pyrrol-1-yl)-pyridine (1.95 g, 7.77 mmol) and triisopropyl borate (2.68 mL, 11.6 mmol) in THF (40 mL) at −78° C. was added n-BuLi (1.6 M in hexane, 4.85 mL, 7.77 mmol) keeping the internal temperature below −65° C. Stirring was continued at −78° C. for 1 h, then more triisopropyl borate (2.68 mL, 11.6 mmol) and n-BuLi (4.85 mL, 7.77 mmol) was added and stirring was continued at −78° C. for 1 h. The reaction mixture was quenched with 1 M NaH2PO4-sol., allowed to quickly (waterbath) warm to ca. 20° C. and stirred for 10 min. Diluted with EtOAc, layers were separated, washed organic layer with brine and dried over Na2SO4. Removal of the solvent in vacuum left the title compound as a yellow foam (2.1 g, 100%, 80% purity), which was used without further purification. MS (ISN) 215.3 [(M−H)−].

1. customthe internal temperature below −65° C
2. stirringstirring
3. waitwas continued at −78° C. for 1 h
4. customThe reaction mixture was quenched with 1 M NaH2PO4-sol
5. stirringstirred for 10 min
6. additionDiluted with EtOAc, layers
7. customwere separated
8. washwashed organic layer with brine
9. dry with materialdried over Na2SO4
10. customRemoval of the solvent in vacuum
11. waitleft the title compound as a yellow foam (2.1 g, 100%, 80% purity), which
12. customwas used without further purification

ORD record

ord-e66b62c8155549b9a1ecc1c0cdab35a1

Source dataset

uspto-grants-2012_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08183262B2