Heptaaryldipyrromethenes are efficiently prepared from ammonium acetate and tetraarylcyclopentadienones in a one-pot cascade process and can be converted into heptaaryl BODIPYs with fluorescent response to environmental acidity.

A series of highly fluorescent, oligo(3,6-phenanthrene ethynylenes) (F1-F7) were synthesized, and their photophysical behavior was systematically investigated. They emitted light with highly emissive quantum yields, up to 0.92. Emissive wavelengths of these compounds relied on the number of phenanthrene blocks existing in the oligomers. Red-shifted emissions were observed as the number of phenanthrenes increased. On the basis of theoretical calculations, helical structures could be formed for F4-F7, indicating that the excimer emissions might be observed for F4-F7 due to the intramolecular π-π stackings of phenanthrenes in the helical structures. However, excimer emissions were only observed for F5-F7 in dilute cyclohexane and for F6 and F7 in dilute methylene chloride, respectively. No excimer emission was observed for F4-F7 in dilute tetrahydrofuran due to the degree of solvation.

9,11,12,14‐Tetraaryldibenzo[f,h]imidazo[1,2‐b]isoquinolines 3a–h were synthesized in moderate yields through the reaction of benzils with 1,3‐diphenyl‐2H‐cyclopenta[l]phenanthren‐2‐ones and ammonium acetate. The photophysical properties of the products in solutions and in thin films were investigated, and strong emissions ranging from 492 to 516 nm were observed in cyclohexane solutions. Moreover, 3h exhibited potential as a versatile fluorescent chemosensor for the detection of solvent polarity, acidity, or trace amounts of nitroaromatics.