Solid-state electronic absorption, fluorescence and13C CPMAS NMR spectroscopic study of thermo- and photo-chromic aromatic Schiff bases
- 1 January 1996
- journal article
- Published by Royal Society of Chemistry (RSC) in Journal of the Chemical Society, Perkin Transactions 2
- No. 11,p. 2293-2296
- https://doi.org/10.1039/p29960002293
Abstract
Solid-state electronic absorption, fluorescence emission and 13C CPMAS spectroscopies have been applied to a series of aromatic Schiff bases displaying both ground and excited state intramolecular proton transfer phenomena. All the results can be explained on the basis of a thermal equilibrium between enolimine and keto–enamine tautomeric forms in the crystalline state. Most of the studied compounds are thermochromic. However, a few are photochromic. The carbon-13 NMR data in the solid state show, in general, residual (13C, 14N) dipolar coupling effects. In certain cases, however, where fast proton transfer occurs in the ground state, these effects are shown to be self-decoupled.Keywords
This publication has 19 references indexed in Scilit:
- Ground‐ and excited‐state prototropic tautomerism in anils of aromatic α‐hydroxy aldehydes studied by electronic absorption, fluorescence and 1H and 13C NMR spectroscopies and semi‐empirical calculationsJournal of Physical Organic Chemistry, 1995
- Tautomerism of representative aromatic α-hydroxy carbaldehyde anils as studied by spectroscopic methods and AM1 calculations. Synthesis of 10-hydroxyphenanthrene-9-carbaldehydeTetrahedron, 1995
- 13C NMR spectroscopic and AM1 study of the intramolecular proton transfer in anils of salicylaldehyde and 2-hydroxynaphthalene-1-carbaldehydeJournal of the Chemical Society, Perkin Transactions 2, 1994
- Excited-state proton transfer reactions II. Intramolecular reactionsJournal of Photochemistry and Photobiology A: Chemistry, 1993
- Excited-state proton transfer reactions I. Fundamentals and intermolecular reactionsJournal of Photochemistry and Photobiology A: Chemistry, 1993
- Organic materials for reversible optical data storageTetrahedron, 1993
- Quadrupolar effects transferred to spin-Progress in Nuclear Magnetic Resonance Spectroscopy, 1992
- Photochromism and thermochromism of schiff bases in the solid state and in rigid glassesTetrahedron, 1987
- High-resolution 13C nuclear magnetic resonance spectra of some solid trans-azobenzene and dyestuff speciesJournal of the Chemical Society, Perkin Transactions 2, 1981
- PHOTOCHROMY AND THERMOCHROMY OF ANILS1The Journal of Physical Chemistry, 1962