1-Methylphenanthro[3,4-b]thiophene: Determination of the tertiary structure in solution and in the crystalline state by NMR spectroscopy and X-ray diffraction

Autor: Milton L. Lee, Raymond N. Castle, M. J. Musmar, Marvin L. Tedjamulia, Robert T. Gampe, Gary E. Martin, Vincent M. Lynch, Stanley H. Simonsen
Rok vydání: 1985
Předmět:
Zdroj: Journal of Heterocyclic Chemistry. 22:545-553
ISSN: 1943-5193
0022-152X
DOI: 10.1002/jhet.5570220268
Popis: 1-Methylphenanthro[3,4-b]thiophene was prepared by the photocyclization of 1-(4′-methyl-2′-thienyl)-2-(2″-naphthyl)ethene. The 1H and 13C-nmr spectra were assigned using two-dimensional 1H/13C heteronuclear chemical shift correlation and relayed coherence transfer (RELAY) experiments. From nuclear Overhauser difference spectra, the H11-C1 methyl-H intramolecular distance was determined to be 2.10 A. The molecule crystallized from chloroform in the monoclinic system, space group P21/c. A total of 3536 unique reflections were measured and the structure was solved by direct methods and refined to a final R = 0.049. The molecule is helical with both chiral forms observed in the crystal. The H11-C1 methyl-H distance in the crystal was 2.12(3)A in excellent agreement with the distance measured in solution by NOE techniques.
Databáze: OpenAIRE
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