A Joint Experimental and Computational Investigation on Homoconjugated Push-Pull Chromophores Derived from 7,7-Diphenylnorbornane
We report hereon the synthesis, spectroscopic properties and computational studies of novel aromatic homoconjugated compounds derived from 7,7-diphenylnorbornane (DPN). The UV/Vis spectra of these compounds show bands corresponding to the respective chromophores as well as new homoconjugation bands and charge transfer absorptions in D–DPN–A push-pull derivatives. Homoconjugation between the aromatic rings strongly depends on the nature of the substitution at the aryl moieties. Therefore, electronic communication by homoconjugation can be easily tuned by controlling the electronic nature and positions of the substituents. The strong homoconjugative interaction is also reflected in the reactivity, NMR spectra and NLO properties of the compounds studied. DFT calculations nicely agree with the experimental data and shed light on the electronic delocalization via homoconjugation.