Acidochromism of the luminescence of bis(4-pyridylethenyl)arenes

A series of C2-symmetrical bis[(E)-2-(4-pyridyl)ethenyl]arenes has been synthesised via two-fold PO-activated olefinations. 1,4-Benzene, 1,4-naphthalene, 9,10-anthracene and 2,2′-diphenyl were used as central units. These fluorescent compounds were freely