Nonlinear optical and energy-level modulation of organic alkynes by click chemistry

A series of novel donor-acceptor chromophores have been successfully synthesized in excellent yield by metal-free [2+2] click chemistry, which was effective in the energy-level modulation of organic the π-conjugation aniline derivatives. Meanwhile, structures of all products were fully characterized by NMR, IR, and MS. UV-vis spectra were enlarged with end-absorptions into the near infrared region in varying degrees by introducing TCNE, TCNQ, F4-TCNQ click reagents and correspondingly electrochemical tests revealed that the energy levels of HOMO and LUMO were effectively tuned. The third order nonlinear optical properties studied at 532/1064 nm with picosecond Z-scan techniques indicated that almost all products exhibited the high NLO properties, especially, for dye c5, exhibiting third-order susceptibility χ(3)=1.83×10−7 esu under laser beam at 1064 nm.

Graphical abstractDownload high-res image (130KB)Download full-size image