反应详情

温度

-65 °C

A solution of n-butylithium in hexane (13.2 mL of 1.6 M, 21 mmol) is added to a stirred solution of 5-bromo-indane (1.06 g 4 mmol) in dry tetrahydrofuran (30 mL) at −75° C. under an argon atmosphere. The mixture is stirred for 30 min at −65° C., then treated with triethylborate (3.07 g, 21 mmol) and stirred for 60 min at −50° C. The resulting mixture is allowed to warm to 0° C. and then treated with a saturated aqueous solution of ammonium chloride (60 mL) and extracted with ethyl acetate (2×80 mL). The combined extracts are dried (Na2SO4), filtered and the solvent is evaporated off under reduced pressure to yield the crude product which is purified by chromatography (silica gel, 50% ethyl acetate in hexaen) and recrystallised from ethyl acetate-hexane to give indan-5-boronic acid as a colourless crystalline solid.

1. stirringstirred for 60 min at −50° C
2. temperatureto warm to 0° C.
3. extractionextracted with ethyl acetate (2×80 mL)
4. dry with materialThe combined extracts are dried (Na2SO4)
5. filtrationfiltered
6. customthe solvent is evaporated off under reduced pressure
7. customto yield the crude product which
8. customis purified by chromatography (silica gel, 50% ethyl acetate in hexaen)
9. customrecrystallised from ethyl acetate-hexane