<i>P</i>
‐Terthienyl‐Functionalized Dithieno[3,2‐
<i>b</i>
:2′,3′‐
<i>d</i>
]phospholes
作者:Chris Jansen Chua、Yi Ren、Monika Stolar、Shirley Xing、Thomas Linder、Thomas Baumgartner
DOI:10.1002/ejic.201301065
日期:2014.4
AbstractA series of dithienophospholes with different P‐thienyl substituents have been synthesized and characterized. Alkyl groups at the 2,6‐positions of the scaffold were introduced for solubility, but were found to also prevent π stacking with this scaffold. Whereas a simple thienyl does not affect the overall photophysics of the dithienophosphole, the installation of terthienyl units creates a considerable subchromophore that can communicate through the phosphole‐typical σ*–π* orbital interaction with the main scaffold. The overall architecture of the terthienyl was also found to have a significant impact on the photophysics of the system. Although a heavily twisted, branched terthienyl does not allow for any intermolecular π‐stacking interaction, the exposed nature of a linear terthiophene does, and gives rise to the formation of excimers in solution, as evident in shifted emission properties as a function of the concentration. Time‐dependent DFT calculations have revealed that in this case, the terthienyl group becomes the main chromophore and the dithienophosphole only plays a supportive role.