Collect. Czech. Chem. Commun. 1994, 59, 1673-1681

Study of Substituted Formylchromones

Hafez M. El-Shaaera, Pavol Zahradníka, Margita Lácováa and Mária Matulováb

a Department of Organic Chemistry, Komensky University, 842 15 Bratislava, Slovak Republic
b Institute of Chemistry, Slovak Academy of Sciences, 842 38 Bratislava, Slovak Republic


Substituted derivatives of 2- and 3-formylchromone were synthesized and studied by IR, 13C and 1H NMR spectroscopy and the AM1 quantum chemical method. Energy and electron distribution calculations confirm the preference of the synplanar conformation in 3-formylchromones. The calculated charges on the carbon atoms correlate well with the experimental 13C chemical shifts. Substituents bonded to the aromatic nucleus have only small effect on the electron structure of the pyrone ring.