tert-Butyl 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole-1-carboxylate → [1-(tert-Butoxycarbonyl)-1H-indol-5-yl]boronic acid

Temperature

23 °C

To N-Boc-indole-5-boronic acid pinacol ester (172 mg, 0.500 mmol, 1.00 equiv) in acetone/H2O (5.0 mL/5.0 mL) at 23° C. was added NH4OAc (193 mg, 2.50 mmol, 5.00 equiv) and NaIO4 (535 mg, 2.00 mmol, 4.00 equiv). After stirring for 24 hr at 23° C., the reaction mixture was concentrated in vacuo to remove acetone. To the residual solution was added EtOAc (5 mL) and the phases were separated. The aqueous phase was extracted with EtOAc (2×5 mL). The combined organic phases are washed with brine (10 mL) and dried (Na2SO4). The filtrate was concentrated in vacuo and the residue was purified by chromatography on silica gel eluting with hexanes/EtOAc 1:1 (v/v) to afford 70.0 mg of the title compound as a colorless solid (54% yield).

1. concentrationthe reaction mixture was concentrated in vacuo
2. customto remove acetone
3. additionTo the residual solution was added EtOAc (5 mL)
4. customthe phases were separated
5. extractionThe aqueous phase was extracted with EtOAc (2×5 mL)
6. washThe combined organic phases are washed with brine (10 mL)
7. dry with materialdried (Na2SO4)
8. concentrationThe filtrate was concentrated in vacuo
9. customthe residue was purified by chromatography on silica gel eluting with hexanes/EtOAc 1:1 (v/v)

ORD record

ord-5f8ace77f2db4ec0a5c460ccb8b655f7

Source dataset

uspto-grants-2015_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09024093B2