1,4-Bis-(α-cyano-4-methoxystyryl)benzene (1a) and 1,4-bis-(α-cyano-4-methoxystyryl)-2,5-dimethoxybenzene (1b) were synthesized by the Knoevenagel reaction of (4-methoxyphenyl)acetonitrile with terephthaldicarboxyaldehyde and 2,5-dimethoxy terephthaldicarhoxyaldehyde, respectively. Both phenylene vinylene oligomers are highly photoluminescent, and the comparison of the emission spectra of the crystalline solids with the ones of the corresponding low-viscosity molecular solutions reveals, particularly in case of 1b, an extremely large bathochromic shift. This effect is consistent with the formation of excimers that are characterized by low-bandgap emission With the objective to control the emission characteristics of these dyes beyond the limiting states of molecular solution and crystalline solid, the investigation of their photophysical characteristics was extended to the liquid crystalline state and the isotropic melt, as well as to blends with isotactic polypropylene.

中文翻译：

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光致发光1,4-双-(α-氰基-4-甲氧基苯乙烯基)苯的合成与性能

通过 Knoevenagel 反应合成 1,4-双-(α-氰基-4-甲氧基苯乙烯基)苯 (1a) 和 1,4-双-(α-氰基-4-甲氧基苯乙烯基)-2,5-二甲氧基苯 (1b) (4-甲氧基苯基)乙腈与对苯二甲二甲醛和 2,5-二甲氧基对苯二甲二甲醛分别。两种亚苯基亚乙烯基低聚物都是高度光致发光的，结晶固体的发射光谱与相应的低粘度分子溶液的发射光谱的比较表明，特别是在 1b 的情况下，具有极大的红移。这种效应与形成以低带隙发射为特征的准分子一致，目的是控制这些染料的发射特性超出分子溶液和结晶固体的极限状态，