Synthesis and properties of highly soluble third-order optically nonlinear chromophores and methacrylate monomer based on distyrylbenzene

A novel series of highly soluble distyrylbenzenes bearing poly(alkyleneoxy) and/or alkylsulfonyl solubilizing substituents has been synthesized using the stereoselective Wadsworth-Emmons reaction as a key step. The corresponding poly(alkyleneoxy) alkylsulfonyl 4,4′-disubstituted distyrylbenzene has been covalently incorporated into an acrylic monomer which has also been successfully co-polymerized with methyl methacrylate (MMA). All the 4,4′-disubstituted distyrylbenzenes and the polyacrylate based co-polymer show excellent solubility, processibility and thermal stability. Importantly, 2-(2-butoxyethoxy)ethoxy-hexylsulfonyl 4,4′-disubstituted distyrylbenzene exhibits only a minor bathochromic shift of the absorption maximum compared to those of the corresponding symmetrically 4,4′-disubstituted distyrylbenzenes; however, its third-order optical nonlinearity derived from Z-scan measurements at 800 nm is approximately twice as large as those of its symmetrically 4,4′-disubstituted counterparts.