Browsing by Subject "Mechanical bond"
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- PublicationOpen AccessA Thiourea-based Rotaxane Catalyst: Nucleophilic Fluorination Phase-Transfer Process Unlocked by the Mechanical Bond(American Chemical Society, 2025-03-18) Martínez Cuezva, Alberto; Berná Cánovas, José; Puigcerver Alarcón, Julio; Juan S. Santiago Dato; Alajarín Cerón, Mateo; Química OrgánicaWe report a five-component clipping approach using activated isophthaloyl-derived esters to synthesize an amide-based thiourea rotaxane. This method overcomes acyl chloride limitations with nucleophilic thiourea threads. The steric hindrance of the mechanical bond enables, for the first time, an interlocked thiourea as a hydrogen-bonding phase-transfer organocatalyst in nu-cleophilic fluorinations. This highlights how mechanical bonds expand thiourea catalysis to processes previously incompatible with conventional catalysts.
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 "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 "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
- PublicationOpen AccessLight-responsive rotaxane-based materials: inducing motion in the solid state(Beilstein Institute for the Advancement of Chemical Sciences, 2023-06-14) Saura Sanmartín, Adrián; Saura Sanmartín, Adrián; Química OrgánicaLight-responsive rotaxane-based solid-state materials are ideal scaffolds in order to develop smart materials due to the properties provided by the mechanical bond, such as control over the dynamics of the components upon application of external stimuli. This perspective aims to highlight the relevance of these materials, by pointing out recent examples of photoresponsive materials prepared from a rotaxanated architecture in which motion of the counterparts and/or macroscopic motion of the interlocked materials are achieved. Although further development is needed, these materials are envisioned as privileged scaffolds which will be used for different advanced applications in the area of molecular machinery.
- PublicationOpen AccessMaximizing the [c2]daisy chain to lasso ratio through competitive self-templating clipping reactions(Royal Society of Chemistry, 2021-11-30) Saura-Sanmartin, Adrian; Pastor Vivero, Aurelia; Martinez-Cuezva, Alberto; Berná Cánovas, José; Química OrgánicaSelf-templating two-component coupling reactions allowed the isolation of two threaded products with different molecular sizes: a lasso-type [1]rotaxane and a [c2]daisy chain rotaxane. Their distribution in the final reaction mixture varies as a factor of the concentration of the reactants. Through this methodology we obtained a large 84-membered cyclic multistation [2]rotaxane.
- 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 AccessMechanically interlocked molecules in metal–organic frameworks(Royal Society of Chemistry, 2022-05-25) Saura-Sanmartin, Adrian; Pastor Vivero, Aurelia; Martinez-Cuezva, Alberto; Cutillas-Font, Guillermo; Alajarín, Mateo; Berná Cánovas, José; Química OrgánicaMechanically interlocked molecules (MIMs) have great potential in the development of molecular machinery due to their intercomponent dynamics. The incorporation of these molecules in a condensed phase makes it possible to take advantage of the control of the motion of the components at the macroscopic level. Metal–organic frameworks (MOFs) are postulated as ideal supports for intertwined molecules. This review covers the chemistry of the mechanical bond incorporated into metal–organic frameworks from the seminal studies to the latest published advances. We first describe some fundamental concepts of MIMs and MOFs. Next, we summarize the advances in the incorporation of rotaxanes and catenanes inside MOF matrices. Finally, we conclude by showing the study of the rotaxane dynamics in MOFs and the operation of some stimuli-responsive MIMs within MOFs. In addition to emphasising some selected examples, we offer a critical opinion on the state of the art of this research field, remarking the key points on which the future of these systems should be focused.
- 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 AccessPhotoswitchable interlocked thiodiglycolamide as a cocatalyst of a chalcogeno-Baylis–Hillman reaction(Royal Society of Chemistry, 2017-03-07) Martinez-Cuezva, Alberto; Saura Sanmartín, Adrián; Nicolas-Garcia, Tomas; Navarro, Cristian; Orenes, Raul-Angel; Alajarín, Mateo; Berná, José; Berná, José; Química OrgánicaEn route to a photoswitchable interlocked catalyst we have proved the ability of thiodiglycolamide to act as a template in the formation of hydrogen-bonded [2]rotaxanes. X-ray diffraction studies reveal the shielding of the sulfide atom by the macrocycle. A series of molecular shuttles are described as having an isomerizable fumaramide and thiodiglycolamide binding sites for controlling the relative ring position at will. By employing these systems as photoregulated catalysts, the TiCl4-mediated chalcogeno-Morita–Baylis–Hillman reaction is tested. In the presence of the maleamide shuttle, in which the sulfide function is encapsulated by the macrocycle, a complete loss in control of the geometry of the produced aldol is observed. The E-aldol adduct is predominantly obtained when the photoisomerized fumaramide shuttle, in which the sulfide function is exposed, is used.
- PublicationOpen AccessSynthesis of ‘Impossible’ Rotaxanes(Wiley-VCH GmbH, 2024-01-17) Saura Sanmartín, Adrián; Química Orgánica‘Impossible’ rotaxanes, which are constituted by interlocked components without obvious binding motifs, have attracted the interest of the mechanically interlocked molecules (MIMs) community. Within the synthetic efforts reported in the last decades towards the preparation of MIMs, some innovative protocols for accessing ‘impossible’ rotaxanes have been developed. This short review highlights different selected synthetic examples of ‘impossible’ rotaxanes, as well as suggests some future directions of this research area.
- PublicationOpen AccessThe Role of Dethreading Process in Pseudorotaxanes and Rotaxanes towards Advanced Applications: Recent Examples(Wiley-VCH, 2023-02-06) Saura-Sanmartín, Adrián; Química OrgánicaRotaxanes are a type of mechanically interlocked molecules (MIMs), constituted by at least a thread surrounded by a wheel, which are widely employed in the research field of artificial molecular machines. Although applications retaining the integrity of the mechanical bond are usually reported, the dethreading of the components can be crucial to develop some advanced applications. Thus, different dethreading strategies have been reported, and advanced applications which require such a process have turned out to be suitable approaches towards machine-like operation. This review article covers recent examples of applications of pseudorotaxanes and rotaxanes in which dethreading processes have a key role to accomplish the desired function.
- 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