Browsing by Subject "Rotaxane"
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- PublicationOpen AccessCooperative fluoride binding in (thio)urea [2]rotaxanes: a mechanical-bond approach to phase‐transfer catalysis(2026-07-05) Puigcerver Alarcón, Julio; Zamora Gallego, José María; Marín Luna, Marta; Alajarín Cerón, Mateo; Martínez Cuezva, Alberto; Berná Cánovas, José; Química Orgánica; Facultades de la UMU::Facultad de QuímicaThe distinctive features of mechanically interlocked molecules have been widely recognised for decades.[1] In this context, our research focuses on integrating the unique structural characteristics of rotaxanes with the catalytic potential of specific functional motifs.[2][3] Hydrogen-bond donor groups such as ureas and thioureas have been extensively employed in anion sensing[4] and anion-binding catalysis.[5] Nevertheless, various strategies have been developed to address their intrinsic limitations and enhance their catalytic performance.[6] In this study, we explore the catalytic potential of tetraamide [2]rotaxanes incorporating urea and thiourea moieties as hydrogen-bonding phase-transfer catalysts in nucleophilic fluorination reactions.[7] We hypothesised that the hydrogen-bond-donating nature of the tetralactam macrocycle could strengthen the interaction of these functional groups with fluoride anions. To test this hypothesis, a series of urea-functionalised rotaxanes were designed and evaluated as catalysts. Our results demonstrate that the cooperative activation of fluoride between the macrocycle and the hydrogen-bond donor significantly improves reaction yields compared with non-interlocked thread analogues.[8] Furthermore, we report a clipping strategy employing activated isophthaloyl-derived esters as key precursors for the synthesis of thiourea-containing rotaxanes. This approach overcomes the incompatibility issues encountered when acyl chloride derivatives were used in the presence of highly nucleophilic thiourea groups. The steric constraints imposed by the mechanical bond enable the use of an interlocked thiourea as a hydrogen-bonding phase-transfer catalyst in nucleophilic fluorination, a reaction previously restricted to urea-based systems.[9] Overall, these findings highlight the pivotal role of the mechanical bond in modulating catalytic activity. References [1] C. J. Bruns, J. F. Stoddart. The Nature of the Mechanical Bond: From Molecules to Machines. Wiley, Weinheim, 2016. [2] A. Martinez-Cuezva, A. Saura-Sanmartin, J. Berna, M. Alajarin. ACS Catal. 2020, 10, 7719. [3] M. Calles, J. Puigcerver, D. A. Alonso, M. Alajarin, A. Martinez-Cuezva, J. Berna, Chem. Sci. 2020, 11, 3629. [4] S. Kundu, T. K. Egboluche, M. A. Hossain. Acc. Chem. Res. 2023, 56, 1320. [5] K. Brak, E. N. Jacobsen. Angew. Chem. Int. Ed. 2013, 52, 534. [6] T. J. Auvil, A. G. Schafer, A. E. Mattson. Eur. J. Org. Chem. 2014, 2633. [7] G. Pupo, V. Gouverneur. J. Am. Chem. Soc. 2022, 144, 5200. [8] J. Puigcerver, J. M. Zamora-Gallego, M. Marin-Luna, A. Martinez-Cuezva, J. Berna. J. Am. Chem. Soc. 2024, 146, 22887. [9] J. Puigcerver, J. S. Dato-Santiago, M. Alajarin, A. Martinez-Cuezva, J. Berna. Org. Lett. 2025, 27, 2873.
PublicationRestrictedFAIR Data for compounds included in the article "Mechanical bonding activation in rotaxane-based organocatalysts".(Universidad de Murcia, 2021-06-01) Pérez Martínez, Jesús de Maria; Puigcerver, Julio; Orlando, Tainara; Pastor Vivero, Aurelia; Martins, Marcos A. P.; Alajarín, Mateo; Martínez Cuezva, Alberto; Berná Cánovas, José; Química Orgánica- PublicationOpen AccessFAIR data for compounds included in the article "Mechanically Planar-to-Point Chirality Transmission in [2]Rotaxanes"(ACS, 2024-03) Puigcerver, Julio; Marin Luna, Marta; Alajarin, Mateo; Martínez Cuezva, Alberto; Berna, Jose; Química Orgánica
- PublicationOpen AccessFAIR Data for compounds included in the article "Reactivity of Glutaconamides Within [2]Rotaxanes: Mechanical Bond Controlled Chemoselective Synthesis of Highly Reactive α-KetoAmides and their Light-Triggered Cyclization" Angew. Chem. Int. Ed. 2023, e202302681(2023-03-23) Perez, Jesus de Maria; Alajarin, Mateo; Martinez-Cuezva, Alberto; Berna, Jose; Química Orgánica
- PublicationOpen AccessFAIR data for compounds included in the article "Ring-to-Thread Chirality Transfer in [2]Rotaxanes for the Synthesis of Enantioenriched Lactams".(Universidad de Murcia, 2022-08-02) López Leonardo, Carmen; Saura Sanmartín, Adrián; Marín Luna, Marta; Alajarín, Mateo; Martínez Cuezva, Alberto; Berná Cánovas, José; Química Orgánica
- PublicationOpen AccessFAIR data for compunds included in the article "Control of the assembly of a cyclic hetero[4]pseudorotaxane from a self-complementary [2]rotaxane"(2023-03-22) Saura-Sanmartin, Adrian; Nicolas-Garcia, Tomas; Pastor, Aurelia; Quiñonero, David; Alajarin, Mateo; Martinez-Cuezva, Alberto; Berna, Jose; Química Orgánica
- PublicationOpen AccessFAIR data for compunds included in the article "Maximizing the [c2]daisy chain to lasso ratio through competitive self-templating clipping reactions"(Universidad de Murcia, 2021-11-30) Saura-Sanmartin, Adrian; Pastor Vivero, Aurelia; Martinez-Cuezva, Alberto; Berná Cánovas, José; Química Orgánica
- PublicationOpen AccessFAIR data for compunds included in the article "Modulating the catalytic activity by the mechanical bond: organocatalysis with polyamide [2]rotaxanes bearing a secondary amino function at the thread"(Universidad de Murcia, 2022-04-06) Perez, Jesus de Maria; Alajarín, Mateo; Martínez Cuezva, Alberto; Berná Cánovas, José; Química Orgánica
- PublicationRestrictedFiles folders for the fair data of the published article Modulating the shuttling motion of [2]rotaxanes built of p-xylylenediamine units through permethylation at the benzylic positions of the ring(2023-10-04) Puigcerver, Julio; Alajarín, Mateo; Berna, José; Martínez Cuezva, Alberto; Química Orgánica
- PublicationOpen AccessMechanical bonding activation in rotaxane-based organocatalysts(Royal Society of Chemistry, 2021) Pérez Martínez, Jesús de Maria; Puigcerver, Julio; Orlando, Tainara; Martins, Marcos A. P.; Alajarín, Mateo; Martinez-Cuezva, Alberto; Berná Cánovas, José; Pastor, Aurelia; Química OrgánicaWe report here the enhanced efficiency as organocatalysts of a series of succinamide-based hydrogen-bonded [2]rotaxanes functionalized with an acyclic secondary amine as the catalytic active site. We also evaluated their catalytic activity, comparing with that of their non-interlocked threads, in an iminium-type process between crotonaldehyde and acetylacetone. The presence of an interlocked polyamide macrocycle notably increased the catalytic activity of the entwined organocatalysts. The mechanized catalysts rapidly form the reactive iminium intermediate with the aldehyde, increasing its population. The hydrogen-bonding interaction established between the macrocycle and the electrophile has been proposed as one of the reasons for the rapid formation and stabilization of this key intermediate.
- PublicationOpen AccessMechanical bonding of rigid MORFs using a tetratopic rotaxane(Royal Society of Chemistry, 2024-05-28) Saura Sanmartín, Adrián; Cutillas Font, Guillermo; Martinez-Cuezva, Alberto; Alajarín, Mateo; Esteban Betegón, Fátima; Pena Sánchez, Pilar; Gándara, Felipe; Berná Cánovas, José; Química Orgánica; Nuevas Arquitecturas en Quı´mica de Materiales, Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC)The preparation of highly rigid cobalt(II)- and copper(II)–organic frameworks incorporating a tetralactam [2]rotaxane as a ligand is described. The interlocked ligand is functionalized with two pairs of carboxylate groups placed at each counterpart, thus limiting its dynamics within the crystal. The solid structure of the metal–organic rotaxane frameworks showed different, unprecedented polycatenation modes of grids, depending on the employed metal, providing great rigidity to the structures. This rigidity has been evaluated by using single crystal X-ray diffraction analyses of the cobalt(II)–organic frameworks embedded in different solvents, observing that the lattices remain unchanged. Thus, this research demonstrates that rigid and robust materials with permanent porosity can be achieved using dynamic ligands.
- PublicationOpen AccessModulating the catalytic activity by the mechanical bond: organocatalysis with polyamide [2]rotaxanes bearing a secondary amino function at the thread(Royal Society of Chemistry, 2022-04-06) Pérez Martínez, Jesús de María; Alajarín, Mateo; Martinez-Cuezva, Alberto; Berná Cánovas, José; Química OrgánicaThe modulation of the catalytic activity of degenerate succinamide-based [2]rotaxanes by changes at their macrocyclic component is disclosed herein. These systems, bearing an acyclic secondary amine function at the thread as the active site and incorporating different polyamide macrocycles, were evaluated as organocatalysts in iminium- and enamine-type processes. The results of kinetic studies clearly show a drastic variation of their catalytic efficiency, which apparently correlated with the electronics and dynamics of the entwined macrocycle.
- PublicationOpen AccessModulating the shuttling motion of [2]rotaxanes built of p-xylylenediamine units through permethylation at the benzylic positions of the ring(Royal Society of Chemistry, 2023-11-03) Puigcerver, Julio; Alajarín, Mateo; Berna, José; Martínez Cuezva, Alberto; Química OrgánicaIn this study, we show the effect of the gem-dimethyl substitution at the four benzylic carbons of the ring on the internal dynamics of two-station [2]rotaxanes. Such structural modification of the polyamide macrocycles promotes a drastic change of the internal dynamics as shown by variable-temperature (VT) 1H NMR experiments. We determined that the shuttling rates of the octamethylated macrocycle along a series of symmetrical threads were significantly faster compared to the non-substituted ring. This effect was particulary pronounced in the -based system, in which the rate was 27 times faster than that of the model system.
- PublicationOpen AccessUrea-based [2]Rotaxanes as Effective Phase-Transfer Organocatalysts: Hydrogen-Bonding Cooperative Activation Enabled by the Mechanical Bond(ACS Publicatins, 2024-07-08) Puigcerver, Julio; Zamora Gallego, José María; Marín Luna, Marta; Martínez Cuezva, Alberto; Berná Cánovas, José; Química Orgánica
- PublicationOpen AccessVersatile control of the submolecular motion of di(acylamino)pyridine-based [2]rotaxanes(2015-03-18) Martínez Cuezva, Alberto; Pastor Vivero, Aurelia; Cioncoloni, Giacomo; Orenes Martínez, Raúl Angel; Alajarín, Mateo; Symes, Mark D.; Berná Cánovas, José; Química Orgánica; WestCHEM, School of Chemistry, University of Glasgow, University Avenue, Glasgow G12 8QQ, UKA cyclic network of chemical reactions has been conceived for exchanging the dynamic behaviour of di(acylamino)pyridine-based rotaxanes and surrogates. X-ray diffraction studies revealed the intercomponent interactions in these interlocked compounds and were consistent with those found in solution by dynamic NMR experiments. This particular binding site was incorporated into a molecular shuttle enabled for accessing two states with an outstanding positional discrimination through chemical manipulation. Furthermore, the ability of the di(acylamino)pyridine domain to associate with external binders with a complementary array of HB donor and acceptor sites was exploited for the advance of an unprecedented electrochemical switch operating through a reversible anion radical recognition process.