Aerial oxidation of protonated aromatic amines. Isolation, X-ray structure, and redox and spectral characteristics of N-containing dyes.

This work reports the results of our investigation on the aerial oxidation of aromatic amines that are promoted by protic acid. While primary aromatic amines produce substituted phenazines as major products, N-phenyl-o-phenylenediamine produces polycyclic aromatic heterocycles like azaacene and secondary and tertiary amines give exclusively the dyes containing a triphenylmethane moiety. Isolation of the compounds and the effects of substitutions on the aromatic rings have been investigated.

One-pot synthesis of linearly fused N-heterocyles from their angular analogues and studies of their redox and electrochromic properties.

In an unusual chemical transformation, the angular heterocyclic compound [1]ClO(4), upon reaction with a primary aromatic amine, is transformed to a linear heterocyclic compound 3 via the angular intermediate [2]ClO(4) in one pot. Characterization of the compounds was primarily achieved by (1)H and (13)C NMR and mass spectral data. Analyses of single-crystal X-ray structures of the representative compounds confirmed their identities.

Synthesis of azoaromatic dyes via redox driven C-N bond fusion.

Two novel organic azo-dyes (2(+)) that feature an intense intramolecular charge transfer transition with end absorption reaching into the NIR region are introduced. Syntheses of these compounds were achieved by an unusual redox-driven C-N bond fusion of the tricyclo azo-aromatic compounds (1(+)). The compounds show reversible electro- as well as proton chromism.