Modification of photophysical behaviour by hydrogen bonding: Indoloquinoxaline and its methylated derivatives

✍ Scribed by J. Waluk; S.J. Komorowski

• Publisher: Elsevier Science
• Year: 1987
• Tongue: English
• Weight: 515 KB
• Volume: 133
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(87)87084-7

✦ Synopsis

Indolo [ 2,3-b] quinoxaline (IQ) and its methyl derivative (6MIQ) drastically change their photophysics in alcohols: fast internal conversion from S, (xx*) is enhanced, while the radiative rates decrease. The strength of the solute-solvent interaction is controlled by the proton-donating ability of the alcohol. Molecular distortion in the excited state is postulated, induced by hydrogen bonding to the pyridine-type nitrogen atom. Hydrogen bond vibrations may provide an efficient channel for excited-state energy dissipation.