Conformational properties and anion complexes of aromatic oligoamide foldamers
In this work, the conformational properties and anion binding of aromatic oligoamide foldamers with 4-9 aromatic units are described. Single crystal Xray diffraction, NMR experiments, mass spectrometry and CD spectroscopy were used to study the conformations and structures of the foldamers, while 1H NMR and ITC titrations were used to elucidate the anion binding of the foldamers. The literature review focuses on the anion binding of foldamers. The structural analysis of five extended foldamers with 7-9 aromatic units showed that the folding motifs are similar to shorter foldamers. The folding is, therefore, predictable and relies mainly on intramolecular hydrogen bonding. The helical and open conformations are retained when foldamers with 5 aromatic units are extended to 7 or 9 aromatic units. A variety of other structures can be obtained by changing the type of a spacer group between the pyridine rings in the foldamer backbone. The binding of small halides is facilitated by the helical preorganization of the foldamers. Five crystal structures of fluoride complexes were obtained. In the complexes, the fluoride is located at the center of a helix. One of the crystal structures was chiral and even exhibited symmetry breaking in the bulk sample. Anion complexes were in line with solid state structural studies. The shorter foldamers with 5 aromatic units had the best affinity to chloride in acetone. A slight increase in the affinity was observed for foldamers with electron withdrawing groups. A favorable entropy increase was the main driving force in the 1:1 chloride complexation. For foldamers with two nitro groups at the foldamer ends, a 1:2 host:guest complex was also unexpectedly observed. Ion mobility mass spectrometry results show that the deprotonated and protonated foldamers and their Cl- and Na+, K+ and Cs+ complexes have only one preferential conformation in the gas phase. Several cation complexes had conformations where the guest did not affect the size of the conformation, but further comparisons to molecular models are needed to make conclusions about the conformations of the complexes. Keywords: foldamers, anion binding, supramolecular chemistry, X-ray diffraction, NMR spectroscopy, ion mobility mass spectroscopy ...
- Artikkeli I: Annala, R., Suhonen, A., Laakkonen, H., Permi, P., & Nissinen, M. (2017). Structural Tuning and Conformational Stability of Aromatic Oligoamide Foldamers. Chemistry: A European Journal, 23 (65), 16671-16680. DOI: 10.1002/chem.201703985
- Artikkeli II: Helttunen, K., Annala, R., Suhonen, A., Nauha, E., Linnanto, J., & Nissinen, M. (2017). Supramolecular chirality and symmetry breaking of fluoride complexes of achiral foldamers. CrystEngComm, 19 (35), 5184-5187. DOI: 10.1039/C7CE01109A
- Artikkeli III: Helttunen, K., Annala, R., Suhonen, A., Iloniemi, J., Kalenius, E., Aragay, G., . . . Nissinen, M. (2019). Oligoamide Foldamers as Helical Chloride Receptors : the Influence of Electron-Withdrawing Substituents on Anion-Binding Interactions. Chemistry : An Asian Journal, 14 (5), 647-654. DOI: 10.1002/asia.201801869
MetadataShow full item record
Showing items with similar title or keywords.
Annala, Riia; Suhonen, Aku; Laakkonen, Heikki; Permi, Perttu; Nissinen, Maija (Wiley-VCH, 2017)A series of aromatic oligoamide foldamers with two or three pyridine-2,6-dicarboxamide units as their main folding motifs and varying aromatic building blocks as linkers have been synthetized to study the effects of the ...
Suhonen, Aku (University of Jyväskylä, 2016)The topic of this thesis is aromatic oligoamide foldamers. The literary review of the thesis discusses the general features of foldamers and their design and then focuses on the specific examples of aromatic oligoamide ...
Suhonen, Aku; Kortelainen, Minna; Nauha, Elisa; Yliniemelä-Sipari, Sanna; Pihko, Petri; Nissinen, Maija (Royal Society of Chemistry, 2016)33 crystal structures (11 unsolvated and 22 solvates) of a series of seven oligoamide foldamers were analysed. The crystal structures revealed that despite the structural and environmental differences the series of foldamers ...
Structural analysis of two foldamer-type oligoamides – the effect of hydrogen bonding on solvate formation, crystal structures and molecular conformation Suhonen, Aku; Nauha, Elisa; Salorinne, Kirsi; Helttunen, Kaisa; Nissinen, Maija (RSC Publishing, 2012)The crystal structures and molecular conformations of two foldamer-type oligoamides were analyzed. One polymorphic form and seven solvates were found for N¹,N³-bis(2-benzamidophenyl)benzene-1,3-dicarboxamide (the benzene ...
Endo-/Exo- and Halogen Bonded Complexes of Conformationally Rigid Cethyl-2-bromoresorcinarene and aromatic N-oxides Puttreddy, Rakesh; Beyeh, Ngong Kodiah; Ras, Robin H.A.; Trant, John; Rissanen, Kari (Royal Society of Chemistry, 2017)The host–guest complexes of conformationally rigid C-ethyl-2-bromoresorcinarene with aromatic N-oxides were studied using single crystal X-ray crystallography. Unlike that of the conformationally more flexible C-ethyl-2- ...