Merocyanines hydrogen-bonded

The design of the spiropyridopyran 14a (Figure 12) was based on the triple hydrogen-bond complementarity between the acetamidopyridopyran unit of 14a or the acetamidopyridone anion unit of the open merocyanine form 14a and guanine. We expected that the equilibrium between the colorless spiropyridopyran and the colored merocyanine would be shifted toward the latter by recognition of... 

Thermotropic liquid-crystalline merocyanine dyes have also been constructed using the same hydrogen-bonding motif. Combined triple hydrogenbonding and 7X-7X interactions between a trialkoxybenzene-functionalized melamine and a merocyanine dye yielded a columnar mesophase [55]. 

Fig. 16 Hydrogen-bond interactions between merocyanine dye 21 and melamine 14...

Fig. 17 Schematic representation of the nine-component hydrogen-bonded assembly between a merocyanine dye (22) and a chiral melamine derivative (23). (Reprinted with permission from Ref. [56]. Copyright 2001 National Academy of Sciences, USA)...

The multiple hydrogen-bonded eomplex of the dithienylethene (107), bearing two melamine moieties, with merocyanine (108) showed J-type exciton eoupling, whieh eould be switched reversibly upon UV/vis irradiation. Upon UV irradiation the J-type exciton in the presence of the bismelamine (109) as a receptor led to the H-type aggregators between (108) and (109). ... 

Zhao, K., Tu, Y., and Luo, Y. (2009) Molecular dynamics and quantum chemistry study on conformations and optical properties of hydrogen bonded dipolar merocyanine dyes. J. Phys. Chem. B,... 

Wurthner, F., S. Yao, B. Heise, and C. Tschierskec. 2001. Hydrogen bond directed formation of hquid-crystaUine merocyanine dye assembUes. Chem. Comm. 2001 2260-2261. 

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