Synthesis and Reduction of Nitrogen-Substituted Diaryl Dihydrophenazine Diradical Dications

A one-pot
synthetic approach to form core-extended N,N′-disubstituted diaryl
dihydrophenazine (DADHP) diradical dications (DRDCs) via chemical
oxidation from aryl-substituted ortho-phenyldiamines
is reported. The isolated N,N′-disubstituted DADHP DRDCs were reduced to their neutral
counterparts with hydrazine. The model system featuring an unsubstituted
fluorene aryl group, 2a, was tested as a photocatalyst
for the polymerization of methyl methacrylate using organocatalyzed
atom transfer polymerization (O-ATRP), which yielded a polymer with
a controlled molecular weight and narrow polydispersity.