H-shaped OPE/OPV oligomers: A new member of 2D-conjugated fluorophore cores

A new class of two-dimensional (2D), pi-conjugated, skewed H-shaped co-oligomers of phenylene vinylene and phenylene ethynylene (11a-d, termed H-mers) were synthesized using Sonogashira coupling and Wittig-Horner reactions as the key steps. Electronic and spectroscopic properties of the H-mers were investigated by UV-vis absorption, fluorescence spectroscopic techniques, and ab initio calculations (HF/321G). Two amino-containing functional H-mers (11b and 11d) were found to exhibit appealing fluorescence sensitivity to selected Bronsted acids and transition-metal ions.