Nucleophile and base differentiation of pyridine with tetrahalocatechols and the formation of manganese( iii )-catecholate and pyridinium-catecholate complexes for the in situ generation of H 2 O 2 from O 2

The structures of two novel pyridinium catecholates are reported by reaction of pyridine with tetrachloro- o -benzoquinone and tetrabromocatechol; with tetrachlorocatechol pyridine acts as a base with the structure of the pyridinium-catecholate salt reported.