Diarylethene-Based CLCs

A major breakthrough in designing high HTP diarylethene dopants was achieved by Li et al. with the development of compound 22-25 (Fig. 5.18) [115-118]. The open and closed isomers of compound 22 exhibited high HTPs of 92 and 77 pm in 5CB, respectively. The relatively small change in HTP only brought 

Apart from the HTP tuning for phase transition and color change, a binaphthyl-derived diarylethene dopant was demonstrated inducing the handedness inversion behavior by Akagi et al. [119]. (R)-26 with two un-bridged binapthyls can induce a right-handed CLC at its open form, while could be switched to left-handed upon 

310 mn far 0 s (orange), 15 s (green), and 60 s (blue). Reproduced with permission from [118]. Copyright 2013 Royal Society of Chemistry 

UV irradiation (Fig. 5.21). It is believed that the reversible handedness inversion originated from the conformation change of binapthyl moieties as well as the stereospecific intermolecular interactions between the binaphthyl moieties and the surrounding nematic LC molecules. This is the first example of diaryIthene dopant capable of handedness inversion in CLCs although it requires specific LC mixture host and only shows low HTPs. 

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