反应详情

温度

-78 °C

To a solution of tert-butyl 6-cyclopropyl-1H-indole-1-carboxylate (1.93 g, 7.51 mmol) and triisopropylborate (2.58 mL, 11.26 mmol) in THF was added LDA (1.5 M in cyclohexane, 7.0 mL, 10.5 mmol) at −78° C. The mixture was stirred at −78° C. for 30 min, 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 aq. 2 N HCl to pH 5 and then extracted with CH2Cl2 (60 mL). The organic layer was dried over Na2SO4 and concentrated to give 1-(tert-butoxycarbonyl)-6-cyclopropyl-1H-indol-2-ylboronic acid as a solid (2.0 g, 88% yield) 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