ISSN:
1572-8854
Keywords:
Planar Schiff base ligands
;
intramolecular N−H...O hydrogen bond
;
quinoid effect
;
X-ray crystal structure
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Physics
Notes:
Abstract The structures of N-(α-naphthyl)-2-oxy-1-naphthaldimine1 and N-(β-naphthyl)-2-oxy-1-naphthaldimine2 have been investigated by X-ray analysis and by spectroscopic methods. Crystals of1 are monoclinic, space groupPn, with cell dimensionsa=10.823(3),b=5.826(2),c=11.899 (3) Å, and β=99.66(3)°. Compound2 crystallizes in the orthorhombic space groupPca21 witha=17.564(3),b=6.314(2), andc=13.663(4) Å. The IR spectra exhibited neither N−H nor O−H stretching frequencies. The existence of theintramolecular hydrogen bonding of N−H...O type was predicted by spectroscopic experiment but unequivocally established by diffraction experiment in both cases1 and2. The molecules1 and2 are significantly planar with considerable quinoid effect at the 2-oxy-naphthaldimine moiety. Although essentially planar, both molecules1 and2 show the delocalization of π-electrons only in the central part of the molecules including C=N imino group with pendent ring carbon atoms.Intermolecular attractions in the crystals belong to weak van der Waals interactions-between discrete planar molecules spatially arranged into the expectedherringbone motif in the solid state.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02018692
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