Novel class of pyrylium dyes with high efficiency in lasing and two-photon absorption fluorescence

We report the synthesis of a promising class of pyrylium dyes concerning laser and two-photon absorption action. Three representatives of this class, 4-(2,4-dichlorophenyl)-2,6-bisphenylpyrylium tetrafluoroborate, 4-phenyl-2,6-bis(4-methoxyphenyl)pyrylium tetrafluoroborate, and 4-(2,4-dichlorophenyl)-2,6-bis(4-biphenyl)pyrylium tetrafluoroborate, were investigated. Each dye was synthesized by a convenient and inexpensive method. Efficient laser action was shown at ∼500, ∼560, ∼615 nm. Changing the conjugation length i.e. the length of the oligophenyl moiety, or introducing various substituents on the aromatic rings, the emission maximum can be controlled. Two-photon absorption induced fluorescence was also observed. These pyrylium dyes constitute excellent candidates for laser technology and two-photon absorption applications.