SYNTHESIS, CRYSTAL STRUCTURE ANALYSIS AND DFT STUDIES OF TWO BENZOSPIROCYCLIC KETONES

Abstract

The functionalized 3H-spiro[isobenzofuran-1,3'-isochromane] skeletons were synthesized in our laboratory with high regioselectivity by palladium-catalyzed intermolecular tandem cycloaddition reaction, two of these derivatives were selected for crystallographic analysis, and the structures of the title compounds were verified by FTIR, 1H NMR and 13C NMR, and MS. The compounds 3a:6'-methoxy-4'-methylene-3H-spiro[isobenzofuran-1,3'-isochromane], C18H16O3 and 3b: 6-fluoro-4-methylene-3'H-spiro[isochromane-3,1'-naphtho[2,3-c]furan ], C21H15O2F. The molecular structure was calculated by density functional theory (DFT) and compared with the x-ray diffraction data. The results of the conformational analysis also showed that the optimized molecular structure obtained by DFT calculations was the same as the optimized molecular structure obtained by X-ray diffraction analysis. In addition, the molecular electrostatic potentials and frontier molecular orbitals of the title compounds were further investigated by using DFT, which revealed the molecular structure features, conformations and some special physicochemical properties of the title compounds.