Abstract
A series of novel thienyl aryleneethynylenes have been prepared by the Sonogashira cross-coupling of dibrominated or diiodinated thiophenes with arylacetylenes. Previously we have investigated the properties of 2,5-bis(phenylethynyl)thiophene, BPET (1), [Siddle et al., New J. Chem., 2007, 31, 841] and in this work we go on to make chemical modification of the central thienyl moiety and examine their influence on the photophysical properties of the arylethynylene thienyl system. Room and low temperature absorption and emission spectra have been recorded, along with fluorescence quantum yields and lifetimes. It is demonstrated that the 1,1-dioxides (3b & 4b) exhibit significant broadening of their fluorescence spectra relative to the other systems, which we attribute to some degree of charge transfer from the peripheral phenyl rings into the electron-deficient thiophene-1,1-dioxide moiety. Furthermore, a non-conjugated fused thiophene system (6b) displays phosphorescence at low temperature, which is rarely observed from aryleneethynylenes. DFT and TD-DFT calculations have been performed to assist understanding the observed properties.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.