Neutral and ionic multiple hydrogen bonded moieties in crystal structure of a one tripodal Schiff base

Structural and spectroscopic properties of solid tris(3-formyl-5-methyl-2-salicylidenamino-ethyl)amine have been investigated. This is a compound containing two moieties with triple Schiff base fragments. One of the moieties has all three neutral intramolecular O–H· · ·N hydrogen bonds, whereas there are only ionic H-bonds in the other moiety. Both moieties form cavities with the amine N atom lone electron pairs inside strongly shielded by three aliphatic wings. The H-bond formed in the Schiff fragments influence the other structural parameters of the nearest aromatic parts of the moieties. 13C and 15N CP/MAS NMR results (chemical shifts) allow to identify two pairs of Schiff and amino nitrogen nuclei thus supporting formation of the two types of moieties in the crystal lattice. q 2003 Elsevier B.V. All rights reserved.