Pyrithione → 2,2'-Thiodipyridine

Participants

Reaction Steps

360 mg (1 mmol) of peracetoquinic acid (32) are taken into solution with stirring in 5 ml of benzene with the addition of 1 ml of oxalyl chloride and 1 drop of DMF for 3 hours. After evaporation to dryness, the residue is taken up in 5 ml of benzene and added with stirring to a suspension of 180 mg (1.1 mmol) of the sodium salt of N-hydroxypyridine-2-thione and 12 mg (0.1 mmol) of DMAP. The reaction mixture is kept refluxing in 10 ml of toluuene under an atmosphere of nitrogen. After 2 hours of heating under reflux, the cooled reaction mixture is filtered on Celite and evaporated to dryness. By flash chromatography on silica (90% of CH2Cl2 ; 10% EtOAc), 306 mg of pyridyl sulfide of formula (34) are obtained in the form of a yellowish oil. Yield 72%.

Provenance & Evidence