Conformational analysis of some dimethylheptanes with the aid of normal coordinate calculations

✍ Scribed by G. A. Crowder; Lorelei Lynch

• Publisher: John Wiley and Sons
• Year: 1985
• Tongue: English
• Weight: 622 KB
• Volume: 6
• Category: Article
• ISSN: 0192-8651
• DOI: 10.1002/jcc.540060616

✦ Synopsis

Infrared spectra were obtained for the series of 2,X-dimethylheptanes (X = 2,3,4,5,6) and were interpreted with the aid of normal coordinate calculations. 2,2-DMH exists as two conformers, with the C, conformer being the only one present in the crystalline solid. 2,3-DMH exists in at least three conformations, all of C1 symmetry. Ambiguities in spectral data indicate that more conformations are present. Two C1 conformations of 2,4-DMH were shown to be present, but an unassigned band may indicate the presence of a third conformer. The presence of at least four conformers, all of C1 symmetry, was shown to be necessary to explain the spectrum of 2,5-DMH. Finally, 2,6-DMH was shown to exist as three conformers, of symmetries C.. Cz, and C1. Vibrational assignments were made for all the probable conformers of all five compounds.