Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
Department of Chemistry, National Taiwan University, 1 Roosevelt Road Section 4, 10617 Taipei, Taiwan.
J Org Chem. 2020 May 1;85(9):5973-5980. doi: 10.1021/acs.joc.0c00414. Epub 2020 Apr 15.
Readily available phenylene-1,3-diamines can be converted into unprecedented analogues of rhodamine and malachite green possessing a central eight-membered ring in three steps. The overall process couples a cyanine chromophore with a urea bridge giving rise to new dyes possessing distinct spectral characteristics: absorption of orange light combined with a weak emission of red light both in solution and in the crystalline state. Their photophysics is governed by the twist of lateral phenyl rings and intramolecular and intermolecular CT transitions.
易得的苯二胺可经三步转化为新型罗丹明和孔雀绿类似物，它们均含有一个中央的八元环。该过程将菁染料发色团与脲桥偶联，得到新的染料，具有独特的光谱特性：在溶液和晶体状态下，吸收橙光并伴有红光弱发射。其光物理性质由侧苯基环的扭转和分子内和分子间 CT 跃迁决定。
