Transient resonance Raman and density functional theory investigation of the 2-fluorenylnitrenium ion

P Zhu; S Y Ong; P Y Chan; K H Leung; D L Phillips

doi:10.1021/ja003839n

Transient resonance Raman and density functional theory investigation of the 2-fluorenylnitrenium ion

J Am Chem Soc. 2001 Mar 21;123(11):2645-9. doi: 10.1021/ja003839n.

Authors

P Zhu¹, S Y Ong, P Y Chan, K H Leung, D L Phillips

Affiliation

¹ Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong S. A. R., P. R. China.

PMID: 11456934
DOI: 10.1021/ja003839n

Abstract

We report a transient resonance Raman spectrum for the 2-fluorenylnitrenium ion obtained after photolysis of 2-azidofluorene. The 10 experimental Raman band frequencies of the transient spectrum show very good agreement with the computed frequencies from BPW91/cc-PVDZ density functional theory calculations for the 2-fluorenylnitrenium ion. Our results confirm the assignment of the approximately 460 nm transient absorption band formed after photolysis of 2-azidofluorene in water/acetonitrile or water solution to the singlet ground electronic state 2-fluorenylnitrenium ion. Our study indicates the 2-fluorenylnitrenium has a large degree of iminocyclohexadienyl cation character with significant delocalization of the charge over both phenyl rings of the fluorene moiety. We compare our results for the 2-fluoreneylnitrenium ion to those previously reported for several other arylnitrenium ions.