A Complete <sup>1</sup>H and <sup>13</sup>C NMR Data Assignment for Three 3-[Substituted methylidene]-1<i>H</i>,3<i>H</i>-naphtho-[1,8-<i>cd</i>]-pyran-1-ones
Dimitar Stoitsov,
Marin Marinov,
Plamen Penchev,
Maria Frenkeva,
Neyko Stoyanov
Affiliations
Dimitar Stoitsov
Department of Analytical Chemistry and Computer Chemistry, Faculty of Chemistry, University of Plovdiv “Paisii Hilendarski”, 4000 Plovdiv, Bulgaria
Marin Marinov
Department of Chemistry and Phytopharmacy, Faculty of Plant Protection and Agroecology, Agricultural University—Plovdiv, 4000 Plovdiv, Bulgaria
Plamen Penchev
Department of Analytical Chemistry and Computer Chemistry, Faculty of Chemistry, University of Plovdiv “Paisii Hilendarski”, 4000 Plovdiv, Bulgaria
Maria Frenkeva
Department of Analytical Chemistry and Computer Chemistry, Faculty of Chemistry, University of Plovdiv “Paisii Hilendarski”, 4000 Plovdiv, Bulgaria
Neyko Stoyanov
Department of Chemical, Food and Biotechnologies, Razgrad Branch, “Angel Kanchev” University of Ruse, 7200 Razgrad, Bulgaria
A combination of 1D and 2D NMR techniques, including HMQC, HSQC, 1H-1H COSY and HMBC, was used to provide completely assigned 1H and 13C NMR data for the structures of three 3-[substituted methylidene]-1H,3H-naphtho[1,8-cd]-pyran-1-ones—3-[(4-methoxyphenyl)methylidene]-1H,3H-naphtho[1,8-cd]-pyran-1-one, 3-[(4-fluorophenyl)methylidene]-1H,3H-naphtho-[1,8-cd]-pyran-1-one and 3-[(thiophen-3-yl)methylidene]-1H,3H-naphtho[1,8-cd]-pyran-1-one. The heteronuclear coupling constants 1–4JCF and 3–4JHF were correspondingly determined. Additionally, IR and Raman spectral data were provided in support of the assigned structures.
