Z. Popović, Vibor Roje, G. Pavlović
Oct 3, 2001
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0
Influential Citations
51
Citations
Journal
Journal of Molecular Structure
Abstract
Abstract The N,N′-bis(1-naphthaldimine)-o-phenylenediamine chloroform (1/1) solvate was prepared from 2-hydroxy-1-naphthaldehyde and 1,2-phenylenediamine in a 2:1 molar ratio and characterized in solution and in the solid state using X-ray single crystal diffractometry, IR and NMR spectroscopy. The structure consists of three structural fragments: two planar, but not coplanar naphthaldimine moieties linked by phenyl ring that derived from o-phenylenediamine. The naphthaldimine fragments contain, along with naphthalene rings, six-membered pseudoaromatic chelate rings, formed by O H⋯N or N H⋯O intramolecular hydrogen bonds that retain planarity of the aldimine fragments. This structure is the first example of the coexistence of two different hydrogen bond types within Schiff base molecule, i.e. the one naphthaldimine part exists in the enolimino form (O H⋯N hydrogen bond of 2.5487(17) A), while the other exists in the ketoamino form (N H⋯O hydrogen bond of 2.5706(19) A). The different hydrogen bond types are related to the different π-electron density distribution within two parts. The amino hydrogen atom forms three-center intramolecular hydrogen bond, which includes the N H⋯O hydrogen bond of 2.5706(19) A within the ketoamino part and also the N H⋯N bond of 2.7238(18) A linking two naphthaldimine fragments of the molecule. IR and 1H and 13C NMR spectral data are consistent with revealed molecular structure in the solid state.