Campus Units

Chemistry

Document Type

Article

Publication Version

Published Version

Publication Date

10-2010

Journal or Book Title

Journal of the American Chemical Society

Volume

132

Issue

45

First Page

16247

Last Page

16255

DOI

10.1021/ja1075162

Abstract

Benzannulation of aromatic molecules is often used to red-shift absorption and emission bands of organic and inorganic, molecular, and polymeric materials; however, in some cases, either red or blue shifts are observed, depending on the site of benzannulation. A series of five platinum(II) complexes of the form (N∧N∧N)PtCl are reported here that illustrate this phenomenon, where N∧N∧N represents the tridentate monoanionic ligands 2,5-bis(2-pyridylimino)3,4-diethylpyrrolate (1), 1,3-bis(2-pyridylimino)isoindolate (2), 1,3-bis(2-pyridylimino)benz(f)isoindolate (3), 1,3-bis(2-pyridylimino)benz(e)isoindolate (4), and 1,3-bis(1-isoquinolylimino) isoindolate (5). For this series of molecules, either a blue shift (2 and3) or a red shift (4 and 5) in absorption and emission maxima, relative to their respective nonbenzannulated compounds, was observed that depends on the site of benzannulation. Experimental data and first principles calculations suggest that a similar HOMO energy level and a destabilized or stabilized LUMO with benzannulation is responsible for the observed trends. A rationale for LUMO stabilization/destabilization is presented using simple molecular orbital theory. This explanation is expanded to describe other molecules with this unusual behavior.

Comments

Reprinted (adapted) with permission from Journal of the American Chemical Society 132 (2010): 16247, doi:10.1021/ja1075162. Copyright 2010 American Chemical Society.

Copyright Owner

American Chemical Society

Language

en

File Format

application/pdf

Included in

Chemistry Commons

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