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A mixture of 2-chloro-3-methylpyridine (6.38 g, 50 mmol) and 4-(trifluoromethyl)benzeneboronic acid (9.59 g, 50 mmol) in DME (75 ml) and Na2CO3 solution (2M, 75 ml) was deoxygenated by bubbling nitrogen through the mixture for 15 mins. Tetrakis (triphenylphosphine) palladium (0) (1.155 g, 1.0 mmol) was added and the reaction was degassed for a further 10 mins. The reaction was heated at reflux for 16 hrs then cooled to rt. The mixture was extracted with EtOAc (×3), the combined extracts were washed with brine, dried (MgSO4), filtered and evaporated. The residue was purified by chromatography (silica, 10-30% EtOAc/isohexane) to give the pyridine (10.75 g, 91%). 1H NMR (360 MHz, CDCl3) δ: 2.36 (3H, s), 7.21-7.26 (1H, m), 7.60-7.72 (5H, m), 8.54-8.55 (1H, m).

1. customwas deoxygenated
2. customby bubbling nitrogen through the mixture for 15 mins
3. customthe reaction was degassed for a further 10 mins
4. temperatureThe reaction was heated
5. temperatureat reflux for 16 hrs
6. extractionThe mixture was extracted with EtOAc (×3)
7. washthe combined extracts were washed with brine
8. dry with materialdried (MgSO4)
9. filtrationfiltered
10. customevaporated
11. customThe residue was purified by chromatography (silica, 10-30% EtOAc/isohexane)
12. customto give the pyridine (10.75 g, 91%)