Jump to main content
Jump to site search

Issue 4, 2001
Previous Article Next Article

The structure, modelling and dynamics of hindered 5,6-diarylacenaphthenes

Author affiliations

Abstract

A series of 5,6-diarylacenaphthenes, 2–4, has been investigated using a variety of theoretical and experimental methods. The purpose of the investigation was to gain a thorough understanding of the dynamics of atropisomer interconversion in these molecules. Quantum chemical calculations were performed at different levels, including Hartree–Fock theory, density functional theory (B3LYP), and a semi-empirical method (AM1). Basis sets used ranged from STO-3G to 6-31+G*. The structures of energy minima and transition states for antisyn interconversion were fully optimised. A geometrical comparison of the single-crystal X-ray structures of syn-2b, anti-2c and anti-2d was made with the results from the calculations, and revealed excellent agreement in most cases. Theoretical barriers to rotation were compared with those derived experimentally by NMR spectroscopy. Again excellent correlation between theoretical and experimental values was found. In the transition states a significant deviation from planarity for the acenaphthene moiety was calculated. The transition state structures indicate why bulky substituents, such as But, in the 3′ and 3″ positions of the peri-aryl rings are not able to prevent atropisomer interconversion. The structures provide a good explanation for the trends observed in experimental barriers to rotation.

Graphical abstract: The structure, modelling and dynamics of hindered 5,6-diarylacenaphthenes

Back to tab navigation

Supplementary files

Publication details

The article was received on 01 Nov 2000, accepted on 24 Jan 2001 and first published on 16 Feb 2001


Article type: Paper
DOI: 10.1039/B008788M
J. Chem. Soc., Perkin Trans. 2, 2001, 459-467

  •   Request permissions

    The structure, modelling and dynamics of hindered 5,6-diarylacenaphthenes

    W. Cross, G. E. Hawkes, R. T. Kroemer, K. R. Liedl, T. Loerting, R. Nasser, R. G. Pritchard, M. Steele, M. Watkinson and A. Whiting, J. Chem. Soc., Perkin Trans. 2, 2001, 459
    DOI: 10.1039/B008788M

Search articles by author

Spotlight

Advertisements