Excited state properties of 2-acrylated anthraquinones

✍ Scribed by N.S. Allen; J.P. Hurley; M. Edge; G.W. Follows; I. Weddell; F. Catalina

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 432 KB
• Volume: 71
• Category: Article
• ISSN: 1010-6030
• DOI: 10.1016/1010-6030(93)85060-l

✦ Synopsis

The absorption, fluorescence and phosphorescence properties of 2-acrylamido and 2-acryloxyanthraquinones are examined in different solvents. The latter has an unusual marked blue-shifted absorption maximum compared with that of the acrylamido derivative. Also, unlike most 2-substituted anthraquinones these molecules exhibit negligible fluorescence.

In the former case, weak phosphorescence in observed which is associated with rapid deactivation of the lowest excited 'VT* state by intersystem crossing to the second excited %n* state followed by internal conversion to the lowest excited 3n+ state and hence radiative emission to the ground-state.

In the latter case, very strong phosphorescence is observed which appears to occur from the second excited 'n7$ state and resembles that of anthraquinone. No evidence is found for a low lying excited 'w* state. This effect is associated with vibronic coupling of the excited 'nrf and '~4 states resulting in rapid intersystem crossing to the %r* state followed by emission to the ground-state.

The data are discussed in the context of their activities for photocrosslinking polymers.