Johannes Froehlich

Novel ene-yne compounds as quadratic nonlinear optical materials

We present a reliable strategy towards title compounds as a novel scaffold for highly nonlinear optical chromophores, using the selective ring fragmentation of thiophenes as a key step. This methodology selectively leads to the Z-isomer of ene-yne substrates, which are subsequently modified by a Huisgen-type cycloaddition yielding the target compounds. To prove the reliability of the developed synthetic route, one target compound was successfully prepared. This material crystallizes in an enantiomorphic space group, despite of being a flexible non-chiral molecule. A detailed discussion regarding the synthetic approach towards title compounds, a determination of material characteristics, including the investigation of the second order nonlinear susceptibility as well as a systematic variation of substituents in order to examine the resulting effects on NLO properties are subject of this presentation.