Multifunctional Polymers Based on Ionic Liquid and Rose Bengal Fragments for the Conversion of CO2 to Carbonates

Supported ionic liquid-like phases (SILLPs) containing Rose Bengal (RB) units are used to develop organocatalytic systems for the cycloaddition of CO2 to epoxides. The activity of the supported RB fragments can be fine-tuned by controlling the nature of the SILLPs (i.e., substitution at the imidazolium ring, cross-linking degree of the polymeric matrix, loading, etc.). Such a catalytic system prepared from cheap, simple, and commercially available components provides high activity and stability, with no decay in activity for at least 10 days of continuous use under flow conditions.Funding for open access charge: CRUE-Universitat Jaume IFunding for open access charge: CRUE-Universitat Jaume

Chiral imidazolium prolinate salts as efficient synzymatic organocatalysts for the asymmetric aldol reaction

Chiral imidazolium l-prolinate salts, providing a complex network of supramolecular interaction in a chiral environment, have been studied as synzymatic catalytic systems. They are demonstrated to be green and efficient chiral organocatalysts for direct asymmetric aldol reactions at room temperature. The corresponding aldol products were obtained with moderate to good enantioselectivities. The influence of the presence of chirality in both the imidazolium cation and the prolinate anion on the transfer of chirality from the organocatalyst to the aldol product has been studied. Moreover, interesting match/mismatch situations have been observed regarding configuration of chirality of the two components through the analysis of results for organocatalysts derived from both enantiomers of prolinate (R/S) and the trans/cis isomers for the chiral fragment of the cation. This is associated with differences in the corresponding reaction rates but also to the different tendencies for the formation of aggregates, as evidenced by nonlinear effects studies (NLE). Excellent activities, selectivities, and enantioselectivities could be achieved by an appropriate selection of the structural elements at the cation and anion

Synergy between supported ionic liquid-like phases and immobilized palladium N-heterocyclic carbene–phosphine complexes for the Negishi reaction under flow conditions

The combination of supported ionic liquids and immobilized NHC–Pd–RuPhos led to active and more stable systems for the Negishi reaction under continuous flow conditions than those solely based on NHC–Pd–RuPhos. The fine tuning of the NHC–Pd catalyst and the SILLPs is a key factor for the optimization of the release and catch mechanism leading to a catalytic system easily recoverable and reusable for a large number of catalytic cycles enhancing the long-term catalytic performance

Rose Bengal Immobilized on Supported Ionic‐Liquid‐like Phases: An Efficient Photocatalyst for Batch and Flow Processes

This is the peer reviewed version of the following article: Rose Bengal Immobilized on Supported Ionic‐Liquid‐like Phases: An Efficient Photocatalyst for Batch and Flow Processes, which has been published in final form at https://doi.org/10.1002/cssc.201901533. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.The catalytic activity of Rose Bengal (RB) immobilized on supported ionic liquid (IL)‐like phases was evaluated as a polymer‐supported photocatalyst. In these systems, the polymer was designed to play a pivotal role. The polymeric backbone adequately modified with IL‐like moieties (supported IL‐like phases, SILLPs) was not just an inert support for the dye but controlled the accessibility of reagents/substrates to the active sites and provided specific microenvironments for the reaction. The structure of SILLPs could be finetuned to adjust the catalytic efficiency of the RB‐SILLP composites, achieving systems that were more active and stable than the related systems in the absence of IL‐like units

Chemoenzymatic synthesis of optically active 2-(2- or 4-substituted-1H-imidazol-1-yl)cycloalcanols. Chiral additives for (L)-proline

Enantiopure substituted imidazoles obtained by enzymatic kinetic resolution can be promising candidates as co-catalysts for aldol reactions catalysed by (L)-proline. These additives seem to form supramolecular complexes with the catalyst through the formation of H-bonds, leading to significant improvement in both the reaction rates and selectivity of the reaction. Herein, we present our results on the use of these substituted trans-2-imidazoyl-cycloalkanols as additives for the (L)-proline catalyzed direct aldol reaction between ketones and aromatic aldehydes

Novel electrolytes based on mixtures of dimethyl Sulfoxide Task Specific Zwitterionic Ionic Liquid and lithium salts: Synthesis and conductivity studies

[EN] Novel methyl sulfoxide imidazolium-based zwitterionic low melting salts was synthesized and characterized. The combination of this functionalized zwitterion and lithium bis(trifluoromethylsulfonyl)amide (LiNTf2) salts at different molar ratios of render to low melting mixtures, which can exhibit an ionic conductivity as high as 3.4 x 10-5 S cm-1 at 30 degrees C or 2.9 x 10-3 S cm- 1 at 120 degrees C and a high thermal decomposition temperature higher than 250 degrees C. The thermal activation energy shown two clearly different Arrhenius trend. For all the mixtures the temperature where the slope of the Arrhenius plot changes is on the range of the melting temperature experimentally observed for the mixture. Below the melting temperature, the values of activation energy are around of two times higher than the values observed for all the mixtures above the melting temperature. On the other hand, in all the mixtures, we have observed that conductivity increases monotonically on the composition of the mixture. These non-volatile and highly polar novel materials can be used for the development of devices targeting high ionic Li-ion conductivity.We want to acknowledge PDC2022-133313-C22 by MCIN/AEI/10.13039/501100011033 and by European Union Next Generation EU/PRTR, Ministerio de Economia y Competitividad Grant Number PID 2019-107137 RB-C21, and by Ayudas investigadores tempranos UNED-Santander (2022V/ITEMP/001) . The authors are grateful to the SCIC of the Universitat Jaume I for technical support.Nuevo, D.; Cuesta, M.; Porcar, R.; Andrio, A.; Garcia-Verdugo, E.; Compañ Moreno, V. (2023). Novel electrolytes based on mixtures of dimethyl Sulfoxide Task Specific Zwitterionic Ionic Liquid and lithium salts: Synthesis and conductivity studies. Chemical Physics. 575. https://doi.org/10.1016/j.chemphys.2023.11204357

Supramolecular Interactions Based on Ionic Liquids for Tuning of the Catalytic Efficiency of (L)-Proline

Noncovalent intermolecular interactions between (l)-proline and ionic liquids (ILs) are key to explain the different catalytic efficiencies observed for this organocatalyst in the aldol reaction carried out in ILs or in the presence of ILs as cosolvents. The catalytic behavior of (l)-proline has been studied in reaction media containing nonchiral (e.g., [Bmim][Cl]) and chiral (e.g., [(R,R)-trans-Cy6-OAc-Im-Bu][Cl]) ILs using the synthesis of 4-hydroxy-4-(4-nitrophenyl)butan-2-one via the aldol reaction between p-nitrobenzaldehyde and acetone as a model reaction. The high degree of supramolecular organization induced by the presence of the ILs or chiral ILs (CILs) can contribute not only to enhance the activity, but also, in some cases, to tune the asymmetric induction.This work was partially supported by MINECO (CTQ2015- 68429-R and CTQ2015-67927-R), Generalitat Valenciana (PROMETEO/2012/020), and UJI-P1-1B2013-37 grants. Cooperation of the SCIC of the UJI for instrumental analyses is acknowledged

Supported Ionic Liquid‐Like Phases (SILLPs) as Immobilised Catalysts for the Multistep and Multicatalytic Continuous Flow Synthesis of Chiral Cyanohydrins

Supported Ionic Liquid‐Like Phases have been found to be efficient organocatalysts for the synthesis of cyanohydrin esters under solvent‐free conditions by an “electrophile‐nucleophile dual activation” based on hydrogen bond formation. The combination of multiple and consecutive multicatalytic steps in a single and integrated cascade process of organocatalytic SILLPs with commercially available supported Candida antarctica lipase type B (CAL‐B) has allowed developing an efficient process for the multicatalytic synthesis of enantiopure cyanohydrins under flow conditions

Dimethyl carbonate as a non-innocent benign solvent for the multistep continuous flow synthesis of amino alcohols

An efficient methodology for the production and resolution of amino alcohols with a low environmental impact has been developed. The system is based on the assembly of three different well compartmentalised catalytic modules allowing the combination of catalytic and biocatalytic elements. Dimethyl carbonate is used as a green but non-innocent solvent, playing a dual role as the solvent and reagent for two out of the three synthetic steps considered. The use of polymer-supported ionic liquids (SILLPS) is key for the development of some of the catalytic systems optimised

Continuous Flow Processes as an Enabling Tool for the Synthesis of Constrained Pseudopeptidic Macrocycles

Herein we report our efforts to develop a continuous flow methodology for the efficient preparation of pseudopeptidic macrocyclic compounds containing the hexahydropyrrolo-[3,4-f]-isoindolocyclophane scaffold and involving four coupled substitution reactions in the macrocyclization process. Appropriate design of a supported base permitted the continuous production of the macrocycles even at large scales, taking advantage of the positive template effect promoted by the bromide anions. In addition, the use of flow protocols allowed a ca. 20-fold increase in productivity as well as reducing the environmental impact almost 2 orders of magnitude, in comparison with the related batch macrocyclization process