Air- Stable Palladium-Catalyzed C-S Bond Formations

General Procedure for the C-S Bond Formations

A 50 mL of reactor was charged with 232.5 mg (0.25 mm) of POPd1, 1.36 g (12.0 mmol) of 3-chloropyridine, 1.18 g (10.0 mmol) of 1-hexanethiol and 1.92 g (20.0 mmol) of NaO-tBu in 15.0 mL of toluene. The resulting mixture was refluxed for 16 h before the mixture was cooled to room temperature and quenched with 100 mL of H2O. The mixture was transferred to a separatory funnel, and extracted with EtOAc (2 X 200 mL). The layers were separated, and organic layer was washed with H2O (100 mL), brine (150 mL), and dried over MgSO4, filtered, and the solvents removed from the filtrate by rotary evaporation. The final product was chromatographed on silica gel using ethyl acetate/hexane (5% volume ratio) as eluant. The eluate was concentrated by rotary evaporation to yield 1.90 g (97% yield) of 3-hexylthiopyridine.

References

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