Boron tribromide → 5-{2-[5-Chloro-2-(hydroxy)-phenyl]cyclopent-1-enyl}-nicotinic Acid Ethyl Ester

5-{2-[5-Chloro-2-(methoxy)-phenyl]-cyclopent-1-enyl}-nicotinic acid ethyl ester (1.500 g, 4.20 mmol) in dry dichloromethane (20 mL) was cooled to −75° C. Boron tribromide, 1M solution in DCM, (40 mL, 40.0 mmol) was added and the reaction mixture stirred at −75° C. for a further hour. The temperature of the reaction was then allowed to rise to −15° C. and kept at −15° C. for a further 2 hours, and was then quenched in ice/water (50 g/50 mL). More dichloromethane (60 mL) was added and the resulting mixture was stirred vigorously for ˜2 hrs. The layers were separated and the organic layer was washed with saturated sodium bicarbonate, dried (magnesium sulphate), filtered and reduced to an oil. The oil was then purified by chromatography to give the title compound (0.800 g, 60%).

1. customto rise to −15° C.
2. customwas then quenched in ice/water (50 g/50 mL)
3. additionMore dichloromethane (60 mL) was added
4. stirringthe resulting mixture was stirred vigorously for ˜2 hrs
5. customThe layers were separated
6. washthe organic layer was washed with saturated sodium bicarbonate
7. dry with materialdried (magnesium sulphate)
8. filtrationfiltered
9. customThe oil was then purified by chromatography

ORD record

ord-810795db9cc04b25a78ef4dbe0f8f26e

Source dataset

uspto-grants-2007_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07232821B2