1,2-Dimethoxyethane → tert-butyl 4-(5-chloro-2-(trifluoromethyl)phenyl)-5,6-dihydropyridine-1(2H)-carboxylate

Temperature

80 °C

A mixture of (5-chloro-2-(trifluoromethyl)phenyl)boronic acid (0.453 g, 2.02 mmol), tert-butyl 4-(((trifluoromethyl)sulfonyl)oxy)-5,6-dihydropyridine-1(2H)-carboxylate (0.669 g, 2.02 mmol), tetrakis(triphenylphosphine)palladium (0.117 g, 0.1 mmol), sodium carbonate (2 M, 5 mL), and 1,2-dimethoxyethane (10 mL) was heated at 80° C. under microwave irradiation for 1.5 h. After cooling to ambient temperature, the mixture was diluted with water (80 mL) and extracted with ethyl acetate (80 mL). The extract was washed with brine (2×50 mL), dried over Na2SO4, filtered, and concentrated under reduced pressure. The resulting residue was chromatographed over silica gel (0-25% EtOAc in hexanes) to give tert-butyl 4-(5-chloro-2-(trifluoromethyl)phenyl)-5,6-dihydropyridine-1(2H)-carboxylate as colorless oil (0.614 g, 84%): 1H NMR (300 MHz, CDCl3) δ 7.59 (d, J=8.5 Hz, 1H), 7.37-7.22 (m, 1H), 7.22 (d, J=1.68 Hz, 1H), 5.60 (br, 1H), 4.02 (br, 2H), 3.61 (br, 2H), 2.34 (br, 2H), 1.50 (s, 9H); MS (ESI+) m/z 306 [M+H]+.

1. temperatureAfter cooling to ambient temperature
2. extractionextracted with ethyl acetate (80 mL)
3. washThe extract was washed with brine (2×50 mL)
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customThe resulting residue was chromatographed over silica gel (0-25% EtOAc in hexanes)

ORD record

ord-76c5d4d6b9f646ef88db5f6b827f1ea4

Source dataset

uspto-grants-2016_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09434727B2