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This density functional theory (DFT) study explores the efficacy of cooperative catalytic systems in enabling the ionic hydrogenation of N2 with H2, leading to NH3 formation. A set of N-heterocyclic carbene-based pincer tungsten/molybdenum metal complexes of the form [(PCP)M1(H)2] (M1 = W/Mo) were chosen to bind N2 at the respective metal centres. Simultaneously, cationic rhodium/iridium complexes of type [Cp*M2{2-(2-pyridyl)phenyl}(CH3CN)]+ (Cp* = C5(CH3)5 and M2 = Rh/Ir), are employed as cooperative coordination partners for heterolytic H2 splitting. The stepwise transfer of protons and hydrides to the bound N2 and intermediate NxHy units results in the formation of NH3. Interestingly, the calculated results reveal an encouraging low range of energy spans ranging from ∼30 to 42 kcal mol−1 depending on different combinations of ligands and metal complexes. The optimal combination of pincer ligand and metal center allowed for an energy span of unprecedented 29.7 kcal mol−1 demonstrating significant potential for molecular catalysts for the N2/H2 reaction system. While exploring obvious potential off-cycle reactions leading to catalyst deactivation, the computed results indicate that no increase in energy span would need to be expected. [ABSTRACT FROM AUTHOR]

This density functional theory (DFT) study explores the efficacy of cooperative catalytic systems in enabling the ionic hydrogenation of N2 with H2, leading to NH3 formation. A set of N-heterocyclic carbene-based pincer tungsten/molybdenum metal complexes of the form [(PCP)M1(H)2] (M1 = W/Mo) were chosen to bind N2 at the respective metal centres. Simultaneously, cationic rhodium/iridium complexes of type [Cp*M2{2-(2-pyridyl)phenyl}(CH3CN)]+ (Cp* = C5(CH3)5 and M2 = Rh/Ir), are employed as cooperative coordination partners for heterolytic H2 splitting. The stepwise transfer of protons and hydrides to the bound N2 and intermediate NxHy units results in the formation of NH3. Interestingly, the calculated results reveal an encouraging low range of energy spans ranging from ∼30 to 42 kcal mol−1 depending on different combinations of ligands and metal complexes. The optimal combination of pincer ligand and metal center allowed for an energy span of unprecedented 29.7 kcal mol−1 demonstrating significant potential for molecular catalysts for the N2/H2 reaction system. While exploring obvious potential off-cycle reactions leading to catalyst deactivation, the computed results indicate that no increase in energy span would need to be expected. [ABSTRACT FROM AUTHOR]

Manganese(I) carbonyl complexes bearing a MACHO‐type ligand (HN(CH2CH2PR2)2) readily react in their amido form with CO2 to generate 4‐membered {Mn−N−C−O} metallacycles. The stability of the adducts decreases with the steric demand of the R groups at phosphorous (R=isopropyl>adamantyl). The CO2‐adducts display generally a lower reactivity as compared to the parent amido complexes. These adducts can thus be interpretated as masked forms of the active amido catalysts and potentially play important roles as off‐loop species or branching points in catalytic transformations of carbon dioxide. [ABSTRACT FROM AUTHOR]

Ruthenium nanoparticles (NPs) immobilized on an amine‐functionalized polymer‐grafted silica support act as adaptive catalysts for the hydrogenation of bicyclic heteroaromatics. Whereas full hydrogenation of benzofuran and quinoline derivatives is achieved under pure H2, introducing CO2 into the H2 gas phase leads to an effective shutdown of the arene hydrogenation while preserving the activity for the hydrogenation of the heteroaromatic part. The selectivity switch originates from the generation of ammonium formate species on the surface of the materials by catalytic hydrogenation of CO2. The CO2 hydrogenation is fully reversible, resulting in a robust and rapid switch between the two states of the catalyst adapting its performance in response to the feed gas composition. A variety of benzofuran and quinoline derivatives were hydrogenated to fully or partially saturated products in high selectivity and yields simply by altering the composition of the feed gas from H2 to H2/CO2. The adaptive catalytic system thus provides controlled access to valuable products using a single catalyst rather than two specific and distinct catalysts with static reactivity. [ABSTRACT FROM AUTHOR]

One approach to recycle homogeneous catalysts is through multiphase catalysis. Multiphase catalysis is not only limited to liquid–liquid multiphase systems but also includes for example solid and liquid phases. In this work, we present a catalyst recycling system based on the crystallization of the entire catalyst phase after the reaction at ambient temperature. Using the green and polar solvent ethylene carbonate, the polar Rh/sulfoXantphos catalyst is trapped in the crystallized ethylene carbonate phase. The product can be decanted under air as the catalyst is stabilized in the solid phase and the entire solid phase including the solvent is recycled. Several reactions such as the hydroformylation of hexene, octene and decene, and the hydrogenation of C14 aldol products were conducted with this system. A TTON of 8627 could be achieved in the hydroformylation of 1-octene with initial turnover frequencies up to 1460 h−1. In addition, the catalyst "pill" was switched between different reactions to show the flexibility of the system. [ABSTRACT FROM AUTHOR]

All catalysts have unique abilities. This is especially true for microbial, enzymatic, and organometallic catalysis, which are often seen as competitive approaches preventing the exploitation of their complementarity. An increasing number of examples show, how using the complete catalytic spectrum can open roads from new substrates to new products. C1‐compounds such as formate, formaldehyde, methanol, or methane from CO2 in combination with green H2 are likely to be future sources of carbon feedstock. This short review highlights how combinations of different catalyst types can facilitate integrated reaction sequences with biogenic substrates to form "bio‐hybrid" fuels and products. [ABSTRACT FROM AUTHOR]

Observing and understanding the phenomena associated with the reaction mechanisms and catalyst deactivation in molecular catalysis is a very challenging task in green chemistry. This knowledge is crucial for applying and scaling catalyzed reactions as well as preventing misproduction at a very early point. Over the years, experimental arrangements have evolved towards analysis of catalysts and reaction products in the so-called operando setups. This contribution reflects on the potential of operando studies to elucidate reaction and deactivation mechanisms in homogeneous catalysis as well as the outstanding opportunities that arise from the application of operando experimental setups. Such setups mostly rely on spectroscopic analysis, optionally coupled with chromatographic techniques that monitor the reaction system. This in turn means that not only the evolution of the reaction substrates and products can be monitored, but also changes of the molecular catalyst species that may affect the catalytic performance. Therefore, this review focusses on techniques to monitor the catalyst under real conditions. In this review, different spectroscopic techniques relevant for monitoring molecular transition metal catalysts in solution are covered, followed by numerical methods used in the chemometrics literature to undertake the challenge of untangling the complex raw signals and allocating them to individual chemical species. Finally, two exemplary case studies of industrially relevant chemical reactions are presented, namely the hydroformylation and the asymmetric hydrogenation. These examples illustrate the significance of the application of both the experimental setups as well as data processing and signal resolution to have an insight into the deactivation of catalytic systems. The operando approach shows high potential for the increased use in future research to develop stable and more selective catalysts which can be applied in greener processes. [ABSTRACT FROM AUTHOR]

The acceptorless dehydrogenation of methanol to carbon monoxide and hydrogen was investigated using homogeneous molecular complexes. Complexes of ruthenium and manganese comprising the MACHO ligand framework showed promising activities for this reaction. The molecular ruthenium complex [RuH(CO)(BH4)(HN(C2H4PPh2)2)] (Ru‐MACHO‐BH) achieved up to 3150 turnovers for carbon monoxide and 9230 turnovers for hydrogen formation at 150 °C reaching pressures up to 12 bar when the decomposition was carried out in a closed vessel. Control experiments affirmed that the metal complex mediates the initial fast dehydrogenation of methanol to formaldehyde and methyl formate followed by subsequent slow decarbonylation. Depending on the catalyst and reaction conditions, the CO/H2 ratio in the gas mixture thus varies over a broad range from almost pure hydrogen to the stoichiometric limit of 1:2. [ABSTRACT FROM AUTHOR]

Copper chromite is decorated with iron carbide nanoparticles, producing a magnetically activatable multifunctional catalytic system. This system (ICNPs@Cu2Cr2O5) can reduce aromatic ketones to aromatic alcohols when exposed to magnetic induction. Under magnetic excitation, the ICNPs generate locally confined hot spots, selectively activating the Cu2Cr2O5 surface while the global temperature remains low (≈80 °C). The catalyst selectively hydrogenates a scope of benzylic and non‐benzylic ketones under mild conditions (3 bar H2, heptane), while ICNPs@Cu2Cr2O5 or Cu2Cr2O5 are inactive when the same global temperature is adjusted by conventional heating. A flow reactor is presented that allows the use of magnetic induction for continuous‐flow hydrogenation at elevated pressure. The excellent catalytic properties of ICNPs@Cu2Cr2O5 for the hydrogenation of biomass‐derived furfuralacetone are conserved for at least 17 h on stream, demonstrating for the first time the application of a magnetically heated catalyst to a continuously operated hydrogenation reaction in the liquid phase. [ABSTRACT FROM AUTHOR]

The hydrogenation of CO2 to methanol was achieved using a catalytic system comprising metal complexes of the form [Mn(CO)2[N(C2H4PR2)] (R=iPr/Ph, [HN(C2H4PPh2)2]=MACHO−Ph) together with Lewis acid additives. Mechanistic studies suggest initial CO2 insertion into a Mn−H bond leads to a formate complex as resting state. By systematically balancing the interaction between the acidic additive and the catalyst, the formate ligand could be removed through esterification to unleash the full catalytic potential. The reaction conditions were optimized on basis of the partial reaction order of relevant compounds. The combination of MACHO−Ph and Ti(OiPr)4 was identified as the most active system with a TON of 160 (p(CO2)=5 bar, p(H2)=160 bar, T=150 °C). Using methanol as solvent and co‐reagent allows the catalytic conversion of CO2/H2 in a liquid phase process comprising only the substrates and products. [ABSTRACT FROM AUTHOR]

The oxidative carbonylation of toluene-2,4-diamine (TDA) with methyl formate (MF), which can be produced from CO2, provides a possible route for the non-phosgene production of isocyanate precursors and enables a valuable utilization of the greenhouse gas. Extensive analysis of the product spectrum has provided detailed insight into the reaction network leading to the target product toluene-2,4-dicarbamate (TDC) and the most important side products. The most prominent one has been identified as methylene-bridged tetracarbamate 5, which is also an interesting precursor for applications in polyurethane chemistry. The side products are caused by three different reaction paths: N-formylation by MF, condensation with in situ formed formaldehyde, and N-methylation by in situ formed dimethyl carbonate (DMC). The influence of the catalyst on product distribution was evaluated for PdCl2/CuCl2 and a large number of heterogeneous Pd-catalysts. The oxidic support materials ZrO2, CeO2 and SiO2 were found to partially suppress the undesired side reactions leading to higher yields of TDC and tetracarbamate 5. The ratio of TDC to 5 was demonstrated to be affected significantly by the choice of the support. The synthetic protocol was extended to the synthesis of dicarbamates from 4,4′-methylenedianiline (MDA) and 2,4-diaminomesitylene (17). These results encourage further investigations into the design of selective catalysts for the production of isocyanate precursors from CO2 as a C1 source. [ABSTRACT FROM AUTHOR]

The selective hydrodeoxygenation of hydroxyacetophenone derivatives is achieved opening a versatile pathway for the production of valuable substituted ethylphenols from readily available substrates. Bimetallic iron ruthenium nanoparticles immobilized on an imidazolium-based supported ionic liquid phase (Fe25Ru75@SILP) show high activity and stability for a broad range of substrates without acidic co-catalysts. [ABSTRACT FROM AUTHOR]

Rhodium nanoparticles immobilized on an acid‐free triphenylphosphonium‐based supported ionic liquid phase (Rh@SILP(Ph3‐P‐NTf2)) enabled the selective hydrogenation and hydrodeoxygenation of aromatic ketones. The flexible molecular approach used to assemble the individual catalyst components (SiO2, ionic liquid, nanoparticles) led to outstanding catalytic properties. In particular, intimate contact between the nanoparticles and the phosphonium ionic liquid is required for the deoxygenation reactivity. The Rh@SILP(Ph3‐P‐NTf2) catalyst was active for the hydrodeoxygenation of benzylic ketones under mild conditions, and the product distribution for non‐benzylic ketones was controlled with high selectivity between the hydrogenated (alcohol) and hydrodeoxygenated (alkane) products by adjusting the reaction temperature. The versatile Rh@SILP(Ph3‐P‐NTf2) catalyst opens the way to the production of a wide range of high‐value cyclohexane derivatives by the hydrogenation and/or hydrodeoxygenation of Friedel–Crafts acylation products and lignin‐derived aromatic ketones. [ABSTRACT FROM AUTHOR]

This article, published in Angewandte Chemie International Edition, discusses the development of an adaptive catalyst for the selective hydrogenation of bicyclic heteroaromatics. The catalyst, based on amine-functionalized ruthenium nanoparticles, can switch its selectivity in product formation by controlling the composition of the feedgas. This selectivity switch is reversible, rapid, and robust, and is attributed to the formation and decomposition of ammonium formate species. The research, conducted by Alexis Bordet, Walter Leitner, and their colleagues, provides valuable insights into the design of catalysts for hydrogenation reactions. [Extracted from the article]

This article, published in Angewandte Chemie, discusses the development of an adaptive catalyst for the selective hydrogenation of bicyclic heteroaromatics. The catalyst, based on amine-functionalized ruthenium nanoparticles, can switch its selectivity in product formation by controlling the composition of the feedgas. This selectivity switch is reversible, rapid, and robust, and is attributed to the formation and decomposition of ammonium formate species. The research, conducted by Alexis Bordet, Walter Leitner, and their colleagues, provides valuable insights into the design of catalysts for hydrogenation reactions. [Extracted from the article]

Telomerization is a versatile tool for synthesizing unsaturated ethers, amines and other molecules starting from 1,3‐dienes and respective nucleophiles. The homogeneously catalyzed reaction has been the subject of academic and industrial research for over 50 years, offering a broad variety of substrates, catalysts and process concepts. This Minireview presents the advances and developments in this field over the last decade. The focus was on the conversion of renewable resources, the synthesis of promising new products and the development of efficient process concepts to combine these. Of great value: Telomerization is a versatile tool for synthesizing unsaturated ethers, amines and other molecules starting from 1,3 dienes and respective nucleophiles. The homogeneously catalyzed reaction has been the subject of academic and industrial research for over 50 years, offering a broad variety of substrates, catalysts and process concepts. This Minireview presents the advances and developments in this field over the last decade. [ABSTRACT FROM AUTHOR]

A titanium oxide supported double metal cyanide (TiO2-DMC) was found to be a highly active catalyst for the reaction of CO2 with propylene oxide to polyethercarbonates, which are useful polymer building blocks for polyurethane applications. The catalyst was prepared by coprecipitation of potassium hexacyanocobaltate(III) and titanium(IV) ethoxide with an excess amount of ZnCl2 under slightly acidic conditions. The TiO2-DMC catalyst provided excellent selectivity to the polymer (>97 %) and outstanding productivity (>500 gpolymer/gcatalyst). The TiO2-support enhanced the Lewis acidity of the DMC catalyst, which facilitated activation of the epoxide and adjusted the binding strength of the polymer chain to the surface of the catalyst. [ABSTRACT FROM AUTHOR]

A recent DFT study of the ruthenium pincer benzoate complex [Ru(PNP)(PhCOO)2] I (PNP = 2,6-bis- (diphenylphosphanyl)lutidine) in its meridional form has revealed mer-I to be a promising catalyst lead structure for the direct insertion of CO2 into the C-H bonds of arenes, such as benzene. After the successful synthesis of I, its solid state structure interestingly and unexpectedly showed the pincer ligand to adopt the facial rather than the meridional coordination mode. Recalculation of the catalytic cycle with fac-I including all relevant local minima and transition states revealed (a) fac-I to be significantly more stable (6.1 kcal mol-1) than mer-I, (b) that the energetic span (ES; i.e. the effective activation barrier) for the cycle with fac-I amounts to 38.8 kcal mol-1, while the cycle with mer-I has an ES of 25.5 kcal mol-1 only. These results are a hint that fac-I is catalytically inactive. Experimental testing of fac-I showed indeed no product formation, which is in full accordance with the computations. To reduce the spatial flexibility of the pincer ligand, its CH2 groups were replaced by O atoms. The resulting complex [Ru(PONOP)(PhCOO)2] II (PONOP = 2,6-bis(diphenylphosphinito)pyridine) was used for the calculation of the catalytic cycle in benzene as the solvent. Gratifyingly, the starting complex mer-II is more stable than fac-II by 1.9 kcal mol-1 in benzene as the solvent. Consequently, mer-II should be available experimentally. As with fac-I, also fac-II generates a catalytic cycle with a high ES (37.1 kcal mol-1), while mer-II generates a cycle with a significantly lower ES (27.2 kcal mol-1) indicating mer-II to be a potentially active catalyst. A possible explanation of the much lower ES in the case of the meridionally coordinated species is found in the stronger interaction of the substrate with the metal center in the arene-s-bond complex. As a result the issue that is created by the mer/fac isomerism can be resolved by creating spatially less flexible structures. [ABSTRACT FROM AUTHOR]

The activation of CO2 is highlighted for two lead-structures of cobalt- and zinc-based homogeneous catalysts used in the copolymerization of epoxides and CO2. Following the activation of CO2 with in situ ATR-IR spectroscopy, a surprisingly facile insertion of CO2 into metal–phenoxide bonds was revealed. [ABSTRACT FROM AUTHOR]

Hybrid sol–gel catalysts of zinc hexacyanocobaltate and SiO2 were prepared by co-precipitation of the double metal cyanide with silica. Hybrid catalysts prepared at moderately acidic conditions showed the best performance with respect to activity, selectivity and stability. The hybrid sol–gel materials displayed high catalytic activity for the copolymerisation of styrene oxide and carbon dioxide (up to 650 molSO (molZn h)−1) and high productivity (575 gPolymer gCatalyst−1). They also displayed good selectivity to the polymeric product (80–87%), while only little cyclic styrene carbonate was formed as side product. A detailed electron microscopy study of the hybrid sol–gel materials showed that the active phase consisted of thin platelets containing the metals in a molar ratio nZn/nCo = 2.1, whereby the double metal cyanide was closely associated with silica. [ABSTRACT FROM AUTHOR]

Hybrid sol–gel catalysts of zinc hexacyanocobaltate and SiO2 were prepared by co-precipitation of the double metal cyanide with silica. Hybrid catalysts prepared at moderately acidic conditions showed the best performance with respect to activity, selectivity and stability. The hybrid sol–gel materials displayed high catalytic activity for the copolymerisation of styrene oxide and carbon dioxide (up to 650 molSO (molZn h)−1) and high productivity (575 gPolymer gCatalyst−1). They also displayed good selectivity to the polymeric product (80–87%), while only little cyclic styrene carbonate was formed as side product. A detailed electron microscopy study of the hybrid sol–gel materials showed that the active phase consisted of thin platelets containing the metals in a molar ratio nZn/nCo = 2.1, whereby the double metal cyanide was closely associated with silica. [ABSTRACT FROM AUTHOR]

Organometallic catalysis is a powerful tool for chemical synthesis, and the field still evolves at a high pace continuously improving efficiencies and opening up new possibilities. However, despite increasing use in specialty and fine chemical production issues of catalyst recovery still hamper broader application and prevent tapping the full potential of this technology on industrial scale. Even though scientists have tackled this problem for decades practicable methods remained scarce. In this contribution we analyse the major challenges of performing organometallic catalysis in continuous flow from a conceptual point of view, and exemplify for recently developed concepts based on near- and supercritical fluids how the integration of molecular and engineering principles can offer new solutions to this persistent problem. [ABSTRACT FROM AUTHOR]

Focuses on a study that introduced supercritical carbon dioxide (scCO...) as a generally applicable reaction medium for rhodium-catalyzed hydroformylation. Materials and methods of the study; Separation of products and catalysts; Monitoring of the rhodium-catalyzed hydroformylation in scCO... by online-GC analysis; Conclusion.

The article offers information on a study according to which, trimethylenemethane-ruthenium (II)-triphos complexes act as highly active catalysts for catalytic carbon-oxygen bond cleavage reactions of lignin model compounds. It discusses the potential of ruthenium-phosphine catalyst that exhibits comparable activity for this cleavage reaction. It informs that theses complexes represent a potential catalytic system for hydrogen transfer reactions.

A new reaction concept that allows one to control the substrate selectivity of a catalytic reaction by supercritical fluid extraction is demonstrated for the hydroformylation of long-chain olefins as a prototypical example. [ABSTRACT FROM AUTHOR]

The front cover picture, provided by the teams of Bardow and Leitner, illustrates the interdisciplinary challenge for sustainable CO2 transformation ranging from the molecular transformation to the overall process design. The team of chemists and engineers exemplifies this for the catalytic hydrogenation of CO2 to formic acid, where the choice of the reaction medium is crucial both for catalyst performance and separation as well as for product isolation. More details on the solved and unsolved issues of the process concept under scrutiny are described in the full paper on pages 307–316 (C. M. Jens, M. Scott, B. Liebergesell, C. G. Westhues, P. Schäfer, G. Franciò, K. Leonhard, W. Leitner, and A. Bardow, Adv. Synth. Catal. 2019, 361, 307–316; DOI: 10.1002/adsc.201801098). [ABSTRACT FROM AUTHOR]

The article discusses the role that catalysts play in the organic synthesis of carbon dioxide (CO2) and hydrogen (H2) into CO2-H2, including in regard to the CO2-H2's role in acting as an ingredient to commercial chemical products. An overview of chemical reactions involving hydrogen and carbon dioxide is provided.

Reports on a multiphase catalysis system devised by scientists which eliminates the difficulty faced in separating out products and recycling the catalytic material. Findings that suggest supercritical carbon dioxide (CO[sub2]) has been found to be useful in multiphase catalysis; Details of the catalytic system which uses ethylene glycol and carbon dioxide; Two immiscible liquids on which the success of classical multiphase catalysis depends; Benefits of using a supercritical CO[sub2].

[Display omitted] • Versatile synthesis of bimetallic M x Ru 100−x @SILP (M = Fe, Co) catalysts. • Systematic comparison of catalytic performances in hydrogenation. • Activity and selectivity depend on the M:Ru ratios, with clear synergistic effects. • For a given selectivity, Co x Ru 100−x more active than Fe x Ru 100-x while requiring less Ru. • Crucial influence of the nature of the "diluting" 3d metal. Bimetallic iron-ruthenium and cobalt-ruthenium nanoparticles with systematic variations in the Fe:Ru and Co:Ru ratios are prepared following an organometallic approach and immobilized on an imidazolium-based supported ionic liquid phase (SILP). Resulting M x Ru 100-x @SILP materials are characterized by electron microscopy, X-ray diffraction and X-ray absorption spectroscopy, confirming the formation of small, well-dispersed and alloyed zero-valent bimetallic nanoparticles. A systematic comparison of the performances of Fe x Ru 100−x @SILP and Co x Ru 100−x @SILP catalysts is made using the hydrogenation of benzilideneacetone as model reaction. The M:Ru ratio is found to have a critical influence on activity and selectivity, with clear synergistic effects arising from the combination of the noble and 3d metals. Co x Ru 100−x @SILP catalysts are significantly more reactive to reach a given selectivity at a systematically higher content of the 3d metal as compared to the Fe x Ru 100−x @SILP catalysts, evidencing a remarkable influence of the nature of the "diluting" 3d metal on the overall performance of the M x Ru 100−x @SILP catalysts. [ABSTRACT FROM AUTHOR]

Abstract: Benzaldehyde lyase is a versatile catalyst for the organic synthesis of enantiopure α-hydroxy ketones. In view of poor solubility and stability of many substrates and products and the prospect of downstream processing, supercritical fluids are explored as an alternative solvent in view of residual stability, activity, and selectivity. Four supercritical fluids were investigated: carbon dioxide, fluoroform, ethane, and sulphur hexafluoride. Water activity and enzyme preparation (pH of lyophilisation) showed to be the main influence parameters. Activity increased with increasing water activity but stability decreased. Furthermore, non-carbon dioxide supercritical fluids give better results in view of stability, activity, and enantioselectivity. Suprisingly, the enantioselectivity is heavily influenced by the reaction from almost racemic in sulphur hexafluoride with up to 90% enantiomeric excess. [Copyright &y& Elsevier]

Review: 198 refs. [ABSTRACT FROM AUTHOR]

Highlights: [•] The combination of zwitterion and phosphotungstate constructed a catalyst. [•] The combined catalyst exhibited high TON and TOF values for expoxidation. [•] The epoxidation can be performed under solventless and ice bath conditions. [•] Strong cooperative effect existed between zwitterions and phosphotungstate. [•] The formation of W/O emulsion by the zwitterion facilitated the reaction. [ABSTRACT FROM AUTHOR]

Abstract: Reversible ionic liquids are a novel class of solvents that combine an effective medium where reactions occur with a ‘built-in’ separation ability for facile recovery of the products and catalysts, making the solvent available for recycle. We report the utility of these solvents in a number of reactions (Claisen–Schmidt condensation, Heck C–C coupling, and CO2 capture) and discuss the effectiveness of the separation. We also provide insight into the challenges and limitations of using these unique solvent systems to couple reactions and separations. [Copyright &y& Elsevier]