反应详情

温度

-78 °C

Into a solution of 1-cyclobutyl-6-(difluoromethoxy)-1H-indole-3-carbonitrile (1.5 g, 5.7 mmol) and triisopropyl borate (2.4 mL, 10.3 mmol) in THF (25 mL) at −78° C. was added LDA (1.5 M in cyclohexane, 5.0 mL, 7.5 mmol). The mixture was stirred at −78° C. for 30 min and then quenched with ice water (60 mL) and stirred for 15 min without cooling. The mixture was extracted with ethyl acetate 1:1 in hexane (20 mL). The aqueous layer was acidified with 2 N aq. HCl to pH 5 and extracted with CH2Cl2 (60 mL). The organic layer was dried over Na2SO4 and concentrated to give 3-cyano-1-cyclobutyl-6-(difluoromethoxy)-1H-indol-2-ylboronic acid as a solid (1.8 g, 60% pure by LCMS) that was used in the next step without further purification.

1. customquenched with ice water (60 mL)
2. stirringstirred for 15 min
3. temperaturewithout cooling
4. extractionThe mixture was extracted with ethyl acetate 1:1 in hexane (20 mL)
5. extractionextracted with CH2Cl2 (60 mL)
6. dry with materialThe organic layer was dried over Na2SO4
7. concentrationconcentrated