Spectroscopy of naphthalene diimides and their anion radicals

Naphthalene diimides 1-4 having different N,N-disubstitution undergo single electron reduction processes either chemically or electrochemically to yield the corresponding radical anion in high yield. This study concentrates on 1, bearing pentyl side chains connected through the diimide nitrogens, an...

Full description

Saved in:
Bibliographic Details
Published inAustralian journal of chemistry Vol. 57; no. 10; pp. 1011 - 1019
Main Authors Andric, G, Boas, JF, Bond, AM, Fallon, GD, Ghiggino, KP, Hogan, CF, Hutchison, JA, Lee, MAP, Langford, SJ, Pilbrow, Troup, GJ, Woodward, CP
Format Journal Article
LanguageEnglish
Published CLAYTON Csiro Publishing 01.01.2004
Subjects
Chemistry
Chemistry, Multidisciplinary
Physical Sciences
Science & Technology
SYSTEM
SHIFT
STATES
ELECTROCHEMICAL DETECTION
DONOR
PHOTOINDUCED ELECTRON-TRANSFER
LIQUID-CRYSTALS
PORPHYRIN
Online AccessGet more information

Cover

More Information
Summary:Naphthalene diimides 1-4 having different N,N-disubstitution undergo single electron reduction processes either chemically or electrochemically to yield the corresponding radical anion in high yield. This study concentrates on 1, bearing pentyl side chains connected through the diimide nitrogens, and compares the results obtained against those bearing isopropyl, propargyl, and phenylalanyl side chains. Compound 1 exhibits mirror image absorption and fluorescence in the near-UV region in CH2Cl2 and dimethylformamide that is typical of monomeric N, N-dialkylsubstituted naphthalene diimides. In toluene, excimer-like emission is observed, which suggests ground-state complexes involving 1 are formed. X-Ray crystallography has been used to characterize 1 in the solid state. Cyclic voltammetry enables the reversible potentials for [NDI](0/-) and [NDI](-/2-) type processes to be measured. Bulk one-electron reduction of 1-4 is characterized by dramatic changes in the absorption and emission spectra. Additionally, highly structured EPR ( electron paramagnetic resonance) signals from dimethylformamide solutions of the radical anions of 1-3 have been obtained and are consistent with coupling between the unpaired electron and the naphthalene diimide nitrogens and hydrogens and the NCH hydrogens of the appropriate side chains. The overall structure of the EPR spectrum is substituent-dependent. These changes in spectroscopic output upon an electronic input may be described as a simple 'on/off' switching mechanism with which to apply a 'bottom-up' approach to molecular device manufacture.
ISSN:0004-9425
1445-0038
DOI:10.1071/CH04130