Boron tribromide → HCID 86761439, compound

Temperature

0 °C

Compound 5a (0.315 g, 0.735 mmol) was dissolved in dichloromethane (5 ml) to obtain a clear colorless solution. This solution was cooled to 0° C. and then boron tribromide (0.283 ml, 2.94 mmol) was added carefully to give a brown solution. The mixture was stirred at room temperature for 2 h and then poured into ice water (25 ml) and extracted with dichloromethane (2×10 ml). The organic phases were combined, washed with a saturated sodium bicarbonate solution (50 ml) and water (50 ml), dried with sodium sulfate and concentrated. The crude product was purified by column chromatography (toluene/ethyl acetate 90:10) to give compound 20 as a yellow oil (0.206 g, 70% yield). 1H NMR (CDCl3): δ 1.86 (s, 3H), 2.80 (dd, J1=5 Hz, J2=16 Hz, 1H), 3.26 (dd, J1=7 Hz, J2=16 Hz, 1H), 3.57 (dd, J1=5 Hz, J2=7 Hz, 1H), 6.66 (dd, J1=2 Hz, J2=8 Hz, 1H), 6.79 (AB, J1=10 Hz, J2=90 Hz, 4H).

1. customto obtain a clear colorless solution
2. customto give a brown solution
3. extractionextracted with dichloromethane (2×10 ml)
4. washwashed with a saturated sodium bicarbonate solution (50 ml) and water (50 ml)
5. dry with materialdried with sodium sulfate
6. concentrationconcentrated
7. customThe crude product was purified by column chromatography (toluene/ethyl acetate 90:10)

ORD record

ord-b62e5c04807b49dca44d7ddf3d87c210

Source dataset

uspto-grants-2011_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08063102B2