Triisopropyl borate → HCID 57356028, compound

Temperature

-30 °C

To a solution of 7-trifluoromethyl-benzo[b]thiophene (0.52 g, 0.0026 mol) in THF (30 mL) at −78° C. was added 2.5 M of n-BuLi in hexane (1.4 mL). The reaction was then slowly warmed up to −30° C. over 30 min. and stirred at this temperature for 10 min prior to recooling to −78° C. and treatment with triisopropyl borate (0.7255 g, 0.0038 mol). The reaction was then slowly warmed up to 0° C. then was quenched with saturated ammonium chloride and the solvent removed in vacuo. To the residue was added aqueous sodium hydroxide (10 mL, 2N solution) followed by water (30 mL) then this mixture was extracted with DCM. The aqueous solution was acidified using dilute sulfuric acid (2N solution), filtered and the residue dried in vacuo to yield 7-trifluoromethylbenzo[b]thiophen-2-boronic acid. 1H NMR (400 MHz, MeOD) δ ppm 7.55 (1H, t, J=7.45 Hz), 7.75 (1H, d, J=7.07 Hz), 8.02 (1H, s) and 8.17 (1H, d, J=−7.83 Hz).

1. customto recooling to −78° C.
2. temperatureThe reaction was then slowly warmed up to 0° C.
3. customthen was quenched with saturated ammonium chloride
4. customthe solvent removed in vacuo
5. additionTo the residue was added aqueous sodium hydroxide (10 mL, 2N solution)
6. extractionthis mixture was extracted with DCM
7. filtrationfiltered
8. customthe residue dried in vacuo

ORD record

ord-b503517e1f9b45298c5e21c91df362a1

Source dataset

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08796455B2