Hydrochloric Acid → 1H-Indol-6-ylboronic acid

温度

0 °C

To a suspension of sodium hydride (130 mg, 5.41 mmol) in anhydrous tetrahydrofuran (20 mL) was added 6-bromoindole (973 mg, 4.96 mmol) (prepared according to W. A. Ayer et al., Tetrahedron 84(14):2919-2924 (1992)) at 0° C. After 15 min. of stirring at 0° C., the reaction was cooled to −78° C., and tert-butyllithium (10.2 mmol, 1.7 M in hexane) (Aldrich) was added dropwise (a white precipitate immediately formed). After 10 min. tri-n-butylborate (2.75 mL, 10.2 mmol) (Aldrich) was added dropwise. The reaction was allowed to warm to room temperature slowly, then the suspension was poured into an ice cold solution of 1N HCl. The organic phase was separated, and the aqueous phase was washed with ether. The combined organic extracts were extracted with 1N NaOH (3×25 mL), and the combined alkaline extracts were acidified to pH 1 with 1N HCl. The product was then extracted with ether, and the combined ether layers were dried over magnesium sulfate and concentrated in vacuo to yield a brownish solid. The product was recrystallized from boiling water to yield 412 mg (50%) white crystals.

1. customprepared
2. customat 0° C
3. temperaturethe reaction was cooled to −78° C.
4. customimmediately formed)
5. temperatureto warm to room temperature slowly
6. customThe organic phase was separated
7. washthe aqueous phase was washed with ether
8. extractionThe combined organic extracts were extracted with 1N NaOH (3×25 mL)
9. extractionThe product was then extracted with ether
10. dry with materialthe combined ether layers were dried over magnesium sulfate
11. concentrationconcentrated in vacuo
12. customto yield a brownish solid
13. customThe product was recrystallized

ORDレコード

ord-67e008b57c9f4b95abef4ab46fc32b57

出典データセット

uspto-grants-2001_10

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US06307056B1