Amphiphile azobenzene

CTABr + amphiphilic azobenzenes. Light and dark reactions are compared... 

Figure 16.5 Reversible switching of amphiphilic azobenzene modified poly(propylene imine) dendrimer on quartz, and at the air-water interface (inset) [74]...

Figure 11.17 Aggregation behavior and photoresponsive properties of an amphiphilic azobenzene dendrimer.

Nishiyama K, Fujihrra M. The cis-trans reversible photoisomerization of an amphiphilic azobenzene derivative in its pure LB film prepared as polyion complexes with polyallylamine. Chem Lett 1988 1257-1260. 

FIG. 6.1 I Amphiphilic fl-cyclodexcrin. amphiphilic azobenzene, and a schematic representation of the molecular arrangement of their inclusion complex in LBK films (adapted with permission from reference SI). 

Nishiyama, K., and Fujihara, M. c/s-rra s-Reversible Photoisomerization of an Amphiphilic Azobenzene Derivative in its Pure LB Film Prepared as Polyion Compleses with Polyallylamin. Chem. Lett. 1257 (1988). 

Schonhoff, M., Chi, L. F., Fuchs, H, and Losche, M. Structural Rearrangements Upon Photoorientation of Amphiphilic Azobenzene Dyes Organized in Ultrathin Films on. Solid Surfaces. Langmuir 11, 163 (1995). 

H. Nakahara, K. Fukuda, M. Shimomura, and T. Kunitake, Molecular arrangements and photoisomerization of amphiphilic azobenzene derivatives in mono- and multilayers, Nippon Kagaku Kaishi 1988, 1001. 

CTABr -I- amphiphilic azobenzenes. Light and dark reactions are compared Aq. micelles affect excimer formation with change in geometry of binding... 

Taguchi, M., Yamada, K., Suzuki, O., Sato, O. and Einaga, Y. (2005) Photoswitchable magnetic nanoparticles of Prussian blue with amphiphilic azobenzene. Chem. Mater., 17, 4554-4559. 

Tachibana, H., Yamaka, Y., Sakai, H., Abe, M., and Matsumoto, M. Structural and Morphological Changes and Polymerization Behaviors of Diacetylene Langmuir-Blodgett Films on Adding Water Soluble Polyallylamine in the Subphase. Polymer 42, 1995 (2001). Nishiyama, K., Kurihara, M. A., and Fujihira, M. Photochromism of Amphiphilic Azobenzene Derivative in its Langmuir-Blodgett Films Prepared as Polyion Complex with Ionic Polymers. Thin Solid Films 179, All (1989). 

Li Y, Deng Y, Tong X, Wang X. 2006. Formation of photoresponsive uniform colloidal spheres from an amphiphilic azobenzene containing random copolymer. Macromole... 

It is of obvious interest to explore the use of other polymerization techniques that, being more tolerant to the experimental conditions and monomers, can produce amphiphilie azobenzene BCPs with no need for post reactions. Notably, Su et al. have reeently reported the synthesis of such an amphiphilic diblock copolymer with PAA as the hydrophilic block using reversible addition-fragmentation transfer (RAFT) polymerization (structure d in Fig. 6.2) (Su et al., 2007). Using RAFT, they prepared PAA capped with dithiobenzoate and used it as the macro-RAFT transfer agent to polymerize the hydrophobic azobenzene polymer successfully. It ean be expected that more amphiphilic azobenzene BCPs will be synthesized using the eontrolled radical polymerization techniques (ATRP and RAFT) because of their simplicity, versatility, and efficiency. 

Hurst and coworkers synthesized an amphiphilic azobenzene derivative, 4-dodecy-4 -(3-phosphate-trimethyleneoxy)azobenzene (DPMA) and incorporated it into DHP vesicles. ions were entrapped in the vesicles during the vesicle formation. Photocontrolled release of ions across the vesicle membrane was conducted by monitoring the K ion concentration released into the solution under UV and visible light irradiation conditions. UV/visible spectroscopic studies confirmed that DPMA molecules were dispersed into the vesicle membrane without aggregation and isomerized reversibly in the vesicle membrane under UV and visible light irradiation. 

Fujiwara El, Yonezawa Y. 1991. Photoelectric response of a black lipid membrane containing an amphiphilic azobenzene derivative. Nature 351 724 726. 

Fujiwara, H., and Yonezawa, Y. (1991) Photoelectric Response of a Black Lipid-Membrane containing an Amphiphilic Azobenzene Derivative, Nature 351, 724-726. 

The amphiphilic azobenzene derivatives (7) containing pyrene unit as fluorescence probe were prepared and their reversibility was examined (Scheme 3)/ Amphiphilic photoresponsive gelation for aromatic solvents was observed in the case of N-glycosylaminoazobenzene derivatives (8)/ Raman spectra of 4-dimethylamino-4 -nitroazobenzene and methyl orange (sodium 4-dimethylamino-4 -sulfonatoazobenzene) were... 

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