0000000001029350

AUTHOR

Riina Aav

Chiral hemicucurbit[8]uril as an anion receptor: selectivity to size, shape and charge distribution

A novel eight-membered macrocycle of the hemicucurbit[n]uril family, chiral (all-R)-cyclohexanohemicucurbit[8]uril (cycHC[8]) binds anions in a purely protic solvent with remarkable selectivity. The cycHC[8] portals open and close to fully encapsulate anions in a 1 : 1 ratio, resembling a molecular Pac-Man™. Comprehensive gas, solution and solid phase studies prove that the binding is governed by the size, shape and charge distribution of the bound anion. Gas phase studies show an order of SbF6− ≈ PF6− > ReO4− > ClO4− > SCN− > BF4− > HSO4− > CF3SO3− for anion complexation strength. An extensive crystallographic study reveals the preferred orientations of the anions within the octahedral cav…

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Formation and trapping of the thermodynamically unfavoured inverted-hemicucurbit[6]uril

Amplification of a thermodynamically unfavoured macrocyclic product through the directed shift of the equilibrium between dynamic covalent chemistry library members is difficult to achieve. We show for the first time that during condensation of formaldehyde and cis-N,N'-cyclohexa-1,2-diylurea formation of inverted-cis-cyclohexanohemicucurbit[6]uril (i-cis-cycHC[6]) can be induced at the expense of thermodynamically favoured cis-cyclohexanohemicucurbit[6]uril (cis-cycHC[6]). The formation of i-cis-cycHC[6] is enhanced in low concentration of the templating chloride anion and suppressed in excess of this template. We found that reaction selectivity is governed by the solution-based template-a…

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Supramolecular Chirogenesis in Bis-Porphyrin: Crystallographic Structure and CD Spectra for a Complex with a Chiral Guanidine Derivative

The complexation of (3aR,7aR)-N-(3,5-bis(trifluoromethyl)phenyl)octahydro-2H-benzo[d]imidazol-2-imine (BTI), as a guest, to ethane-bridged bis(zinc octaethylporphyrin), bis(ZnOEP), as a host, has been studied by means of ultraviolet-visible (UV-Vis) and circular dichroism (CD) absorption spectroscopies, single crystal X-ray diffraction, and computational simulation. The formation of 1:2 host-guest complex was established by X-ray diffraction and UV-Vis titration studies. Two guest BTI molecules are located at the opposite sides of two porphyrin subunits of bis(ZnOEP) host, which is resting in the anti-conformation. The complexation of BTI molecules proceed via coordination of the imine nitr…

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Synthesis and Characterisation of Chiral Triazole-Based Halogen-Bond Donors: Halogen Bonds in the Solid State and in Solution

A general platform for the synthesis of various chiral halogen-bond (XB) donors based on the triazole core and the characterisation of factors that influence the strength of the halogen bond in the solid state and in solution are reported. The characterisation of XB donors in the solid state by X-ray crystallography and in solution by 1H NMR titration can be used to aid the design of new XB donors. We describe the first example of a XB between iodotriazoles and thioureas in solution. In addition, the enantiodiscrimination of acceptors in solution through halogen-bond participation is described.

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Thiourea Organocatalysts as Emerging Chiral Pollutants: En Route to Porphyrin-Based (Chir)Optical Sensing

Environmental pollution with chiral organic compounds is an emerging problem requiring innovative sensing methods. Amino-functionalized thioureas, such as 2-(dimethylamino)cyclohexyl-(3,5-bis(trifluoromethyl)phenyl)thiourea (Takemoto’s catalyst), are widely used organocatalysts with virtually unknown environmental safety data. Ecotoxicity studies based on the Vibrio fischeri luminescence inhibition test reveal significant toxicity of Takemoto’s catalyst (EC50 = 7.9 mg/L) and its NH2-substituted analog (EC50 = 7.2–7.4 mg/L). The observed toxic effect was pronounced by the influence of the trifluoromethyl moiety. En route to the porphyrin-based chemosensing of Takemoto-type thioureas, their s…

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Carbonyl hypoiodites from pivalic and trimesic acid and their silver(I) intermediates

The first tris(O–I–N) carbonyl hypoiodites have been synthesised based on trimesic acid and pyridine or 4-methylpyridine, with their structures definitively confirmed by single crystal X-ray diffraction (SCXRD). The more soluble carbonyl hypoiodites based on pivalic acid have also been studied via NMR, SCXRD, and computational analyses, enabling the study of the direct silver(I) precursor and intermediates of the resulting carbonyl hypoiodites generated using a range of substituted pyridines. peerReviewed

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Chiral hemicucurbit[8]uril as an anion receptor: selectivity to size, shape and charge distribution

A novel eight-membered macrocycle of the hemicucurbit[n]uril family, chiral (all-R)-cyclohexanohemicucurbit[8]uril (cycHC[8]) binds anions in a purely protic solvent with remarkable selectivity. The cycHC[8] portals open and close to fully encapsulate anions in a 1 : 1 ratio, resembling a molecular Pac-Man™. Comprehensive gas, solution and solid phase studies prove that the binding is governed by the size, shape and charge distribution of the bound anion. Gas phase studies show an order of SbF6− ≈ PF6− > ReO4− > ClO4− > SCN− > BF4− > HSO4− > CF3SO3− for anion complexation strength. An extensive crystallographic study reveals the preferred orientations of the anions within the octahedral cav…

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Template-controlled synthesis of chiral cyclohexylhemicucurbit[8]uril

Enantiomerically pure cyclohexylhemicucurbit[8]uril (cycHC[8]), possessing a barrel-shaped cavity, has been prepared in high yield on a gram scale from either (R,R,N,N')-cyclohex-1,2-diylurea and formaldehyde or cycHC[6]. In either case, a dynamic covalent library is first generated from which the desired cycHC can be amplified using a suitable anion template.

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Large Azobenzene Macrocycles : Formation and Detection by NMR and MS Methods

Azobenzene macrocycles are widely investigated as potential drug delivery systems and as part of molecular machines due to their photo-responsive properties. Herein, we detect the formation of a series of new azobenzene macrocycles that feature up to eight switchable repeating units. High-resolution mass spectrometry and ion mobility (IM) mass spectrometry experiments and 1H and diffusion-ordered spectroscopy (DOSY) NMR are used to detect the presence of the macrocycles that contain 10 to 40 aromatic rings in the gas phase and solution, respectively. The responsiveness of the Z-to-E photo-switching of the smallest of the macrocycles, exhibiting two azobenzene units and in total 10 aromatic …

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Solution- and gas-phase study of binding of ammonium and bisammonium hydrocarbons to oxacalix[4]arene carboxylate

Oxacalixarenes represent a distinctive class of macrocyclic compounds, which are closely related to the parent calixarene family, offering binding motifs characteristic of calixarenes and crown ethers. Nevertheless, they still lack extensive characterization in terms of molecular recognition properties and the subsequent practical applicability. We present here the results of binding studies of an oxacalix[4]arene carboxylate macrocycle toward a variety of organic ammonium cationic species. Our results show that the substituents attached to the guest ammonium compound largely influence the binding strengths of the host. Furthermore, we show that the characteristic binding pattern changes up…

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Chiral hemicucurbit[8]uril as an anion receptor: selectivity to size, shape and charge distribution† †Electronic supplementary information (ESI) available: MS, NMR, dynamic NMR and computational details and a DFT-based video of complexation. CCDC 1514736–1514741, 1521388. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c6sc05058a Click here for additional data file. Click here for additional data file. Click here for additional data file.

Chiral (all-R)-cyclohexanohemicucurbit[8]uril binds anions in a 1 : 1 ratio in pure methanol like a molecular Pac-Man™ with remarkable selectivity based on the size, shape and charge distribution of the anion.

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CCDC 1569570: Experimental Crystal Structure Determination

Related Article: Elena Prigorchenko, Sandra Kaabel, Triin Narva, Anastassia Baškir, Maria Fomitšenko, Jasper Adamson, Ivar Järving, Kari Rissanen, Toomas Tamm, Riina Aav|2019|Chem.Commun.|55|9307|doi:10.1039/C9CC04990H

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CCDC 1514740: Experimental Crystal Structure Determination

Related Article: Sandra Kaabel, Jasper Adamson, Filip Topić, Anniina Kiesilä, Elina Kalenius, Mario Öeren, Mart Reimund, Elena Prigorchenko, Aivar Lõokene, Hans J. Reich, Kari Rissanen, Riina Aav|2017|Chemical Science|8|2184|doi:10.1039/C6SC05058A

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CCDC 1514737: Experimental Crystal Structure Determination

Related Article: Sandra Kaabel, Jasper Adamson, Filip Topić, Anniina Kiesilä, Elina Kalenius, Mario Öeren, Mart Reimund, Elena Prigorchenko, Aivar Lõokene, Hans J. Reich, Kari Rissanen, Riina Aav|2017|Chemical Science|8|2184|doi:10.1039/C6SC05058A

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CCDC 1522088: Experimental Crystal Structure Determination

Related Article: Mikk Kaasik, Sandra Kaabel, Kadri Kriis, Ivar Järving, Riina Aav, Kari Rissanen, Tönis Kanger|2017|Chem.-Eur.J.|23|7337|doi:10.1002/chem.201700618

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CCDC 2081478: Experimental Crystal Structure Determination

Related Article: Nele Konrad, Matvey Horetski, Mariliis Sihtm��e, Khai-Nghi Truong, Irina Osadchuk, Tatsiana Burankova, Marc Kielmann, Jasper Adamson, Anne Kahru, Kari Rissanen, Mathias O. Senge, Victor Borovkov, Riina Aav, Dzmitry Kananovich|2021|Chemosensors|9|278|doi:10.3390/chemosensors9100278

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CCDC 1522089: Experimental Crystal Structure Determination

Related Article: Mikk Kaasik, Sandra Kaabel, Kadri Kriis, Ivar Järving, Riina Aav, Kari Rissanen, Tönis Kanger|2017|Chem.-Eur.J.|23|7337|doi:10.1002/chem.201700618

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CCDC 1522081: Experimental Crystal Structure Determination

Related Article: Mikk Kaasik, Sandra Kaabel, Kadri Kriis, Ivar Järving, Riina Aav, Kari Rissanen, Tönis Kanger|2017|Chem.-Eur.J.|23|7337|doi:10.1002/chem.201700618

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CCDC 1522087: Experimental Crystal Structure Determination

Related Article: Mikk Kaasik, Sandra Kaabel, Kadri Kriis, Ivar Järving, Riina Aav, Kari Rissanen, Tönis Kanger|2017|Chem.-Eur.J.|23|7337|doi:10.1002/chem.201700618

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CCDC 1522085: Experimental Crystal Structure Determination

Related Article: Mikk Kaasik, Sandra Kaabel, Kadri Kriis, Ivar Järving, Riina Aav, Kari Rissanen, Tönis Kanger|2017|Chem.-Eur.J.|23|7337|doi:10.1002/chem.201700618

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CCDC 1514738: Experimental Crystal Structure Determination

Related Article: Sandra Kaabel, Jasper Adamson, Filip Topić, Anniina Kiesilä, Elina Kalenius, Mario Öeren, Mart Reimund, Elena Prigorchenko, Aivar Lõokene, Hans J. Reich, Kari Rissanen, Riina Aav|2017|Chemical Science|8|2184|doi:10.1039/C6SC05058A

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CCDC 1514739: Experimental Crystal Structure Determination

Related Article: Sandra Kaabel, Jasper Adamson, Filip Topić, Anniina Kiesilä, Elina Kalenius, Mario Öeren, Mart Reimund, Elena Prigorchenko, Aivar Lõokene, Hans J. Reich, Kari Rissanen, Riina Aav|2017|Chemical Science|8|2184|doi:10.1039/C6SC05058A

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CCDC 1522082: Experimental Crystal Structure Determination

Related Article: Mikk Kaasik, Sandra Kaabel, Kadri Kriis, Ivar Järving, Riina Aav, Kari Rissanen, Tönis Kanger|2017|Chem.-Eur.J.|23|7337|doi:10.1002/chem.201700618

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Chiral hemicucurbit[8]uril as an anion receptor: selectivity to size, shape and charge distribution

Chiral (all-R)-cyclohexanohemicucurbit[8]uril binds anions in a 1 : 1 ratio in pure methanol like a molecular Pac-Man™ with remarkable selectivity based on the size, shape and charge distribution of the anion.

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CCDC 1522086: Experimental Crystal Structure Determination

Related Article: Mikk Kaasik, Sandra Kaabel, Kadri Kriis, Ivar Järving, Riina Aav, Kari Rissanen, Tönis Kanger|2017|Chem.-Eur.J.|23|7337|doi:10.1002/chem.201700618

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CCDC 1522080: Experimental Crystal Structure Determination

Related Article: Mikk Kaasik, Sandra Kaabel, Kadri Kriis, Ivar Järving, Riina Aav, Kari Rissanen, Tönis Kanger|2017|Chem.-Eur.J.|23|7337|doi:10.1002/chem.201700618

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CCDC 1522079: Experimental Crystal Structure Determination

Related Article: Mikk Kaasik, Sandra Kaabel, Kadri Kriis, Ivar Järving, Riina Aav, Kari Rissanen, Tönis Kanger|2017|Chem.-Eur.J.|23|7337|doi:10.1002/chem.201700618

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CCDC 1522084: Experimental Crystal Structure Determination

Related Article: Mikk Kaasik, Sandra Kaabel, Kadri Kriis, Ivar Järving, Riina Aav, Kari Rissanen, Tönis Kanger|2017|Chem.-Eur.J.|23|7337|doi:10.1002/chem.201700618

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CCDC 1522083: Experimental Crystal Structure Determination

Related Article: Mikk Kaasik, Sandra Kaabel, Kadri Kriis, Ivar Järving, Riina Aav, Kari Rissanen, Tönis Kanger|2017|Chem.-Eur.J.|23|7337|doi:10.1002/chem.201700618

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CCDC 2051302: Experimental Crystal Structure Determination

Related Article: Irina Osadchuk, Nele Konrad, Khai-Nghi Truong, Kari Rissanen, Eric Clot, Riina Aav, Dzmitry Kananovich, Victor Borovkov|2021|Symmetry|13|275|doi:10.3390/sym13020275

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CCDC 1521388: Experimental Crystal Structure Determination

Related Article: Sandra Kaabel, Jasper Adamson, Filip Topić, Anniina Kiesilä, Elina Kalenius, Mario Öeren, Mart Reimund, Elena Prigorchenko, Aivar Lõokene, Hans J. Reich, Kari Rissanen, Riina Aav|2017|Chemical Science|8|2184|doi:10.1039/C6SC05058A

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CCDC 1514736: Experimental Crystal Structure Determination

Related Article: Sandra Kaabel, Jasper Adamson, Filip Topić, Anniina Kiesilä, Elina Kalenius, Mario Öeren, Mart Reimund, Elena Prigorchenko, Aivar Lõokene, Hans J. Reich, Kari Rissanen, Riina Aav|2017|Chemical Science|8|2184|doi:10.1039/C6SC05058A

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CCDC 1514741: Experimental Crystal Structure Determination

Related Article: Sandra Kaabel, Jasper Adamson, Filip Topić, Anniina Kiesilä, Elina Kalenius, Mario Öeren, Mart Reimund, Elena Prigorchenko, Aivar Lõokene, Hans J. Reich, Kari Rissanen, Riina Aav|2017|Chemical Science|8|2184|doi:10.1039/C6SC05058A

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