Synthesis of Phototrappable Shape-Shifting Molecules for Adaptive Guest Binding
| Autor: | Alexander R. Lippert, Vasken L. Keleshian, Atsushi Naganawa, Jeffrey W. Bode |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
education.field_of_study
Porphyrins Valence (chemistry) Light Molecular Structure Chemistry Stereochemistry Population Oligonucleotides General Chemistry Biochemistry Catalysis Colloid and Surface Chemistry Bisporphyrin bullvalene Structural isomer Molecule education Dynamic equilibrium Binding affinities |
| Zdroj: | Journal of the American Chemical Society. 132:15790-15799 |
| ISSN: | 1520-5126 0002-7863 |
| DOI: | 10.1021/ja107314p |
| Popis: | We have designed and synthesized oligosubstituted bullvalenes 1 and 2 as adaptive molecules that can change their shapes in order to bind tightly to a suitable guest. By incorporation of a photolabile o-nitroveratryloxycarbonate (NVOC) group into bullvalenes 1 and 2, tightly binding species can be selectively isolated from a population of hundreds of interconverting structural isomers. Spontaneous strain-assisted Cope rearrangements allow these shape-shifting molecules to exist in a dynamic equilibrium of configurationally distinct valence isomers, as revealed by dynamic NMR and HPLC studies. When NVOC bullvalenes 1 and 2 were exposed to UV light, the cleavage of the NVOC group resulted in a mixture of static isomers of the corresponding bullvalone. Binding studies of NVOC bisporphyrin bullvalene 1 demonstrated that the dynamic isomeric equilibrium shifted in the presence of C(60), favoring configurations with more favorable binding affinities. Irradiation of a mixture of 1 and C(60) with UV light and isolation of the major static isomer yielded an isomer of bisporphyrin bullvalone with a binding affinity for C(60) that was ∼2 times larger than that of the nonadapted isomer bisporphyrin bullvalone 41. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|