Water → 3-Cyclopent-1-enyl-5-nitro-2-(2,2,2-trifluoro-ethoxy)-pyridine

Temperature

80 °C

To a stirred solution of 3-bromo-5-nitro-2-(2,2,2-trifluoro-ethoxy)-pyridine (Example 1a) (6 g, 19.9 mmol) in DMF (30 mL) was added 2-(1-cyclopenten-1-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (CAN 287944-10-9) (4.64 g, 23.9 mmol) and K2CO3 (8.2 g, 59.8 mmol) at 25° C. and the reaction mixture was degassed with argon over 30 min. To this was added PdCl2 (dppf)2 dichloromethane complex (814 mg, 1.1 mmol) and the reaction mixture was heated to 80° C. for 20 h. The reaction mixture cooled to 25° C., water (50 mL) was added, the mixture was extracted with ethyl acetate (4×50 mL), washed with water (200 mL), brine, dried with Na2SO4 and concentrated. The crude material was purified by column chromatography (Combi-Flash, 40 g, 2% dichloromethane/hexane) to get the title compound (2.5 g, 43.51%) as pale white solid; NMR complies.

1. customthe reaction mixture was degassed with argon over 30 min
2. additionTo this was added PdCl2 (dppf)2 dichloromethane complex (814 mg, 1.1 mmol)
3. temperatureThe reaction mixture cooled to 25° C.
4. extractionthe mixture was extracted with ethyl acetate (4×50 mL)
5. washwashed with water (200 mL), brine
6. dry with materialdried with Na2SO4
7. concentrationconcentrated
8. customThe crude material was purified by column chromatography (Combi-Flash, 40 g, 2% dichloromethane/hexane)

ORD record

ord-d3009ed53de948fe940fe28660ce9bb5

Source dataset

uspto-grants-2013_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08455501B2