- A Cholesterol Containing pH-Sensitive Bistable [2]Rotaxane
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A non-symmetrical pH-sensitive bistable [2]rotaxane that bears a cholesterol unit and a tetraphenylmethane group as stopper groups was designed and synthesized in 18 steps. The successful formation of the rotaxane was proven by NMR spectroscopy and MS/MS. Besides a permanent cationic alkylated triazolium unit, the axle contains a secondary amine that can act as a second pH-sensitive binding site for a crown ether. Depending on the protonation state of this amine function, the crown ether reversibly changes its position by moving between the two binding sites along the axle, as revealed by NMR spectroscopy. A pH-sensitive bistable [2]rotaxane was synthesized and characterized by NMR spectroscopy and MS/MS. Besides an alkylated triazolium ion, the axle contains a secondary amine that acts as a second pH-sensitive binding site for a crown ether. Depending on the protonation state of this amine function, the crown ether reversibly changes its position by moving between two binding sites on the axles.
- Berg, Martin,Nozinovic, Senada,Engeser, Marianne,Lützen, Arne
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p. 5966 - 5978
(2015/09/22)
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- Synthesis and topological determination of hexakis-substituted 1,4-ditritylbenzene and nonakis-substituted 1,3,5-tritritylbenzene derivatives: Building blocks for higher supramolecular assemblies
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Based on trityl moieties, novel organic building blocks have been prepared and structurally investigated. Substituted hexaphenyl-p-xylene (1,4-ditritylbenzene) as well as extended analogues thereof were prepared. Furthermore, a new family based on a 1,3,5-tritritylbenzene motif, connecting three trityl groups through a formal mesitylene unit, was developed. Both families were further converted through six-and nine-fold substitution reactions, respectively, to yield potent molecular building blocks for supramolecular assemblies.
- Plietzsch, Oliver,Schade, Alexandra,Hafner, Andreas,Huuskonen, Juhani,Rissanen, Kari,Nieger, Martin,Muller, Thierry,Braese, Stefan
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supporting information
p. 283 - 299
(2013/02/25)
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- Nanostructured columnar and cubic liquid-crystalline assemblies consisting of unconventional rigid mesogens based on triphenylmethanes
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Liquid-crystalline (LC) molecules of unconventional shapes that form columnar and micellar cubic structures have been synthesized using triarylmethyl moieties as building blocks. The molecules have bowl- and dumbbell-shape. Despite the rigidity and bulkiness of the triarylmethyl moieties, the molecules form columnar and micellar cubic LC phases. The bowl-shaped molecules containing one triarylmethyl moiety show LC phases. The LC temperature ranges of the dumbbell-shaped molecules containing two triarylmethyl moieties connected by rigid rods are wider than those of bowl-shaped molecules containing one triarylmethyl moiety. The UV-vis spectroscopy of the dumbbell-shaped molecules having a terphenyl moiety reveals that the terphenyl moieties aggregate in the mesophase.
- Hatano, Tsukasa,Kato, Takashi
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p. 8368 - 8380
(2008/12/21)
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- Foldamers as dynamic receptors: Probing the mechanism of molecular association between helical oligomers and rodlike ligands
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A dynamic binding mechanism allows the association of dumbbell-shaped ligand 2 with helical folded oligo(m-phenyleneethynylene)s 1 (see schematic representation). Association constants are oligomer length specific, with a maximum value for the icosamer an
- Tanatani, Aya,Hughes, Thomas S.,Moore, Jeffrey S.
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p. 325 - 328
(2007/10/03)
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