Phosphorus pentachloride → Pyridine-3-sulfonyl chloride

Participants

Reaction Steps

3-pyridylsulfonic acid 5-5 (30 g, 0.188 mole) was added to PCl5 (46.8 g, 0.225 mole) suspended in 150 mL toluene and heated to reflux ovemight. The suspension was cooled and concentrated to yield a yellow oil, which was diluted with benzene, filtered through a pad of celite and concentrated to give 5-6 as a yellow oil that was used in the next step without purification. 1H NMR (300 MHz, CDCl3) a 9.27 (1H, s), 8.98 (1H, d, 8.35 (1H, d), 7.62 (1H, dd).

Provenance & Evidence