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Ab initio and molecular mechanics calculations on imine derivatives: A study of the rotational barriers and the development of MM2 parameters

✍ Scribed by Maria Kontoyianni; Andrew J. Hoffman; J. Phillip Bowen

Publisher: John Wiley and Sons
Year: 1992
Tongue: English
Weight: 676 KB
Volume: 13
Category: Article
ISSN: 0192-8651
DOI: 10.1002/jcc.540130107

No coin nor oath required. For personal study only.

✦ Synopsis

The application of molecular mechanics methods for the study of structures has become a standard approach to conformational analysis. The MM2 force field has been extended to include imines. In general, a diverse group of aliphatic and aromatic imine structures can now be treated. The rotational energy profiles and barriers to N-substituted imines about the C,,,2-C,,,2 single bonds adjacent to C=N functional group were calculated via a6 initio MO theory. Information obtained from the quantum mechanical calculations at the 3-21G, 631G*, and MP4/631G'//631G' levels was used both to study the phenomena involved and to parameterize MM2. The syn-anti isomerization was also studied, and the mechanistic pathways have been evaluated. In cases where the comparison with experimental data can be made, the agreements are good.

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