engleski

Synthesis and structure of N,N-butylene- and N,N-hexylenebis(2-oxy-1-naphthaldimine)

The title compounds were synthesized in the reaction of 2-hydroxy-1-naphth-aldehyde and corresponding aliphatic diamines. Standard TGA and DSC procedures were applied to characterize both Compounds 1 and 2. The stereochemistry of the compounds in solid state was determined by single crystal X-ray diffraction. Compound 1: C26H24N2O2, orthorhombic, space group Pbca, a = 8.142(2) A, b = 9.097(3) A, c = 28.812(8) A, R = 0.032. Compound 2: C28H28N2O2, orthorhombic, space group Pbcn, a = 23.738(2) A, b = 8.9933(8) A, c = 10.4206(8) A, R = 0.038. The molecules of both Compounds 1 and 2 have imposed centre of inversion in the middle of the aliphatic chain bridging two naphthaldimine moieties. Well known crystallographic D2h bond length pattern as well as quinoid effect were observed in fused ring system in both cases. In both Schiff bases the N-H---O type of intramolecular hydrogen bond is established. An additional intermolecular three-centre hydrogen bond links the molecules in Compound 1.

naphthaldimine Schiff bases; quinoid effect; intra- and intermolecular hydrogen bond; X-ray structure determination; thermal analysis

nije evidentirano