Allosteric Guest Binding in Chiral Zirconium(IV) Double Decker Porphyrin Cages.

Autor: Bruekers JPJ; Radboud University Institute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands., Hellinghuizen MA; Radboud University Institute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands., Vanthuyne N; Aix Marseille Univ CNRS Centrale Marseille iSm2 Marseille France., Tinnemans P; Radboud University Institute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands., Gilissen PJ; Radboud University Institute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands., Buma WJ; University of Amsterdam Van 't Hoff Institute for Molecular Sciences Science Park 904 1098 XH Amsterdam The Netherlands.; Radboud University Institute for Molecules and Materials FELIX Laboratory Toernooiveld 7c 6525 ED Nijmegen The Netherlands., Naubron JV; Aix Marseille Univ CNRS Centrale Marseille Spectropole FR1739 Marseille France., Crassous J; Univ Rennes CNRS Institut des Sciences Chimiques de Rennes ISCR-UMR 6226 35000 Rennes France., Elemans JAAW; Radboud University Institute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands., Nolte RJM; Radboud University Institute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands.
Jazyk: angličtina
Zdroj: European journal of organic chemistry [European J Org Chem] 2021 Jan 26; Vol. 2021 (4), pp. 607-617. Date of Electronic Publication: 2021 Jan 05.
DOI: 10.1002/ejoc.202001392
Abstrakt: Chiral zirconium(IV) double cage sandwich complex Zr(1) 2 has been synthesized in one step from porphyrin cage H 2 1. Zr(1) 2 was obtained as a racemate, which was resolved by HPLC and the enantiomers were isolated in >99.5 % ee. Their absolute configurations were assigned on the basis of X-ray crystallography and circular dichroism spectroscopy. Vibrational circular dichroism (VCD) experiments on the enantiomers of Zr(1) 2 revealed that the chirality around the zirconium center is propagated throughout the whole cage structure. The axial conformational chirality of the double cage complex displayed a VCD fingerprint similar to the one observed previously for a related chiral cage compound with planar and point chirality. Zr(1) 2 shows fluorescence, which is quenched when viologen guests bind in its cavities. The binding of viologen and dihydroxybenzene derivatives in the two cavities of Zr(1) 2 occurs with negative allostery, the cooperativity factors α (=4 K 2 /K 1 ) being as low as 0.0076 for the binding of N,N' -dimethylviologen. These allosteric effects are attributed to a pinching of the second cavity as a result of guest binding in the first cavity.
Competing Interests: The authors declare no conflict of interest.
(© 2020 The Authors. European Journal of Organic Chemistry published by Wiley-VCH GmbH.)
Databáze: MEDLINE
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