Studies in dipyridyl chemistry. VII. Sulfur trioxide sulfonation of γ,γ′-dipyridyl

Abstract

Reaction of γ,γ′-dipyridyl with sulfur trioxide at room temperature gives γ,γ′-dipyridyld'isulfotrioxide, which latter on heating at 200° gives γ,γ′-dipyridyl-sulfonic acid. Salts of γ,γ′-dipyridyl-3-sulfonic acid are prepared, among them the potassium, sodium, barium, and 3-cyano-γ,γ′-dipyridyl salts.