1-(3',4'-dimethoxyphenyl)-2-hydroxycyclobutene-3,4-dione 3-fluoro-N,N-dimethylaniline | 141063-15-2

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吡啶及其衍生物
• 英文名称: 1-(3',4'-dimethoxyphenyl)-2-hydroxycyclobutene-3,4-dione 3-fluoro-N,N-dimethylaniline
• CAS: 141063-15-2
• 化学式: C₈H₁₀FN*C₁₂H₁₀O₅
• 分子量: 373.381
• InChiKey: XGIRHFHAAAXRQP-UHFFFAOYSA-N

反应信息

• 作为反应物：
  描述：

  1-(3',4'-dimethoxyphenyl)-2-hydroxycyclobutene-3,4-dione 3-fluoro-N,N-dimethylaniline 在 原甲酸三正丁基酯 作用下， 以 异丙醇 为溶剂， 反应 1.5h， 以59%的产率得到
  参考文献：
  名称：

  Squaraine chemistry. Synthesis, characterization, and optical properties of a class of novel unsymmetrical squaraines: [4-(dimethylamino)phenyl](4'-methoxyphenyl)squaraine and its derivatives

  摘要：

  A class of novel, unsymmetical squaraines, namely [4-(dimethylamino)phenyl](4'-methoxyphenyl)squaraine and its derivatives USq-1-13, which were designed to improve the spectral response of photoconductive squaraines in xerographic devices in the visible region, have been synthesized by condensation of 1-aryl-2-hydroxycyclo-butene-3,4-diones 3-5 with various N,N-dimethylaniline derivatives. The effects of reaction solvent, temperature, and concentration of drying reagent (tributyl orthoformate) on the yield of squaraine formation were studied systematically using the synthesis of USq-1 as a model reaction. Results show that an optimal yield can be obtained when the condensation reaction is carried out in refluxing 2-propanol (90 min) in the presence of greater-than-or-equal-to 3 equiv of tributyl orthoformate. Esterification of the cyclobutenedione reactant is shown to be the major side reaction of the synthesis. The ester formed in the side reaction was not detectable during our side-product analysis, but it was shown to undergo further arylation with the aniline reactant to produce an isolable polymeric side product. The scope of the squaraine synthesis was examined by reacting 3-5 with various aniline derivatives. Our data consistently show that the reaction condition developed in this work is superior to that reported earlier by Sprenger and Ziegenbein, where squaraines were prepared in an azeotropic cosolvent containing benzene and 1-butanol. The improvement in yield is attributable to the use of 2-propanol as a reaction solvent, which suppresses the side (esterification) reaction of the reactant by a steric effect and also minimizes the secondary reaction of the squaraine product by lowering the reaction temperature. Since 3-5 were synthesized by a [2 + 2] cycloaddition reaction, the synthesis reported here represents the first general synthesis of photoconductive squaraine where the use of the expensive squaric acid is avoided. Studies of the spectroscopic and solid-state properties of USq-1-13 reveal that their properties are similar to those of bis[4-(dimethylamino)phenyl]squaraine (2), a model photoconductive squaraine. A general hypsochromic shift on the solution absorption maxima of USq-1-13, relative to that of 2, is observed and is attributable to the incorporation of a less electron-releasing methoxy group in these compounds. This hypsochromic shift has led to a similar hypsochromic shift in the solid-state absorption, resulting in an increase in absorptivity at 400-500 nm and an improvement in spectral response in the visible region for USq-1-13 in xerographic photoreceptor devices.

  DOI：

  10.1021/jo00038a010