An alternative synthesis of benzobis(imidazolium) salts via a 'one-pot' cyclization/oxidation reaction sequence

Article abstract of DOI:10.1016/j.tetlet.2006.05.076

Cyclization of N-aryl and N-alkyl 2,5-diamino-1,4-benzoquinonediimines using paraformaldehyde under acidic conditions followed by oxidation with catalytic amounts of Pd(OAc)₂ afforded their respective benzobis(imidazolium) salts in yields of 48