Sulfur trioxide pyridine complex is the compound with the formula C5H5NSO3. It is a colourless solid that dissolves in polar organic solvents. It is the adduct formed from the Lewis base pyridine and the Lewis acid sulfur trioxide. The compound is mainly used as a source of sulfur trioxide, for example in the synthesis of sulfate esters from alcohols:
- ROH + C5H5NSO3 → [C5H5NH]+[ROSO3]-
It is also an activating electrophile in a Parikh-Doering oxidation.
- ^ Thomas T. Tidwell "Sulfur Trioxide–Pyridine" Encyclopedia of Reagents for Organic Synthesis 2001, John Wiley & Sons. doi:10.1002/047084289X.rs139m. Article Online Posting Date: April 15, 2001
- ^ Jekishan R. Parikh, William v. E. Doering (1967). "Sulfur trioxide in the oxidation of alcohols by dimethyl sulfoxide". J. Am. Chem. Soc. 89 (21): 5505–5507. doi:10.1021/ja00997a067.