Hydrogen-bonded 2-hydroxybenzalazines: Complete assignment of1H and13C NMR spectra

Abstract

The 80 MHz 1H NMR and 20 MHz 13C NMR spectra of eleven substited benzalazines (subsituenst: α-methyl, α,α′-dimethyl, 2-hydroxy, 2,2′-dihydroxy, 4-n-octyloxy, 4,4′-di-n-octyloxy) possessing mesogenic acivity have been assigned using a variety of one-dimensional techniques. These include homonuclear NOE measurements, selective heteronuclear 13C{1H} NOE difference spectroscopy, singlefrequency off-resonance decoupling, spin—echo multiplicity sorting (SEFT) and long-range heteronuclear coupling constant determintion via both gated decoupling and selective excitation (DANTE).