p-Toluenesulfonic acid → 2-Chloro-6-[5-ethyl-2-(2-pyridyl)oxazolidin-3-yl]-4-(trifluoromethyl)pyridine-3-carbonitrile

Participants

Reaction Steps

Pyridine-2-carboxaldehyde (207 mg, 1.9 mmol) was added to a toluene solution (15 mL) of 2-chloro-6-(2-hydroxybutylamino)-4-(trifluoromethyl) pyridine-3-carbonitrile (400 mg, 1.3 mmol) followed by a catalytic amount of para-toluene sulfonic acid (50 mg). The reactants were refluxed for 6 hours in a Dean-Stark apparatus, concentrated under reduced pressure, adsorbed onto silica and purified using a neutral alumina column, eluting with a mobile phase of 10% ethyl acetate in hexane. 2-Chloro-6-[5-ethyl-2-(2-pyridyl)oxazolidin-3-yl]-4-(trifluoromethyl) pyridine-3-carbonitrile (Compound 19) was isolated as a solid in 46% yield. mp 99-102° C.

Provenance & Evidence