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The application of biocatalysis has become essential in both academic and industrial domains for the asymmetric synthesis of chiral amines, and it serves as an alternative tool to transition‐metal catalysis and complements traditional chemical methods. It relies on the swift expansion of available processes, primarily as a result of advanced tools for enzyme discovery, combined with high‐throughput laboratory evolution techniques for optimizing biocatalysts. This concept paper explores the utilization of non‐conventional media such as ether‐type solvents, deep eutectic solvents, and micellar catalysis to enhance biocatalytic reactions for chiral amine synthesis. Each section focuses on the unique properties of these media, including their ability to stabilize enzymes, alter substrate solubility, and modulate enzyme selectivity. The paper aims to provide insights into how these innovative media can overcome traditional limitations, offering new avenues for sustainable and efficient chiral amine production through biocatalytic processes. [ABSTRACT FROM AUTHOR]

This account summarizes the impact that the quest for sustainability is having on the field of organic polyconjugate molecules and polymers for plastic (opto)electronics. While at the proof-of-concept level, the design criteria as well as the preferred synthetic strategies to access new and improved materials have been dominated by the need for performance. The ongoing transition from the lab environment to the industrial scale imposes strict limitations on the cost and overall environmental impact of new materials. We here summarize our efforts on the development of new design criteria and synthetic strategies aimed at improving sustainability – without compromising performance – in organic polyconjugated molecules. The article is composed of three sections: Introduction and motivation, sustainability through improved synthetic methods and through improved design. Outline 1 Introduction and Motivation 2 Sustainable Reaction Methods 2.1 The New Tools: Reactions in Aqueous Solution of Surfactants 2.2 Intrinsically More Sustainable Reactions: Direct Arylation 2.3 Sustainable Multistep Protocols: Combining Micellar, Solventless, and Mechanochemical Methods 3 Sustainability as a Design Criterion: De Novo Design 4 Conclusion [ABSTRACT FROM AUTHOR]

The adoption of green chemistry principles has ushered in significant advancements in environmental safety and cost efficiency across various synthetic processes. One notable area of improvement lies in reducing the hazardous waste generated by using organic solvents in organic reactions. In contrast, the utilization of water as a solvent has emerged as a sustainable and environmentally friendly alternative. Micellar catalysis, driven by tailor-made surfactants, has played a pivotal role in enhancing water’s efficacy as a solvent in organic synthesis. These designer surfactants boast unique structures that enhance the solubility of organic compounds in water and act as initiators or stabilizers for nanoparticle catalysts, facilitating efficient catalysis. Micelles function as nanoreactors, creating localized high concentrations of reactants that lead to unprecedented reaction rates and exceptional selectivity. This review underscores the plethora of sustainable protocols that have yielded outstanding results by leveraging aqueous micellar chemistry in pharmaceutical synthesis. Moreover, the review explores the integration of nanocatalysis using readily available first-row transition metals, with a particular emphasis on the role of surfactants in stabilizing the catalyst. The versatility of the proline-based surfactant PS-750-M as a ligand or capping agent, enabling ligand-free metal nanocatalysis, is also addressed. Lastly, the review addresses current challenges and future avenues in green chemistry, stressing the importance of ongoing research and innovation. [ABSTRACT FROM AUTHOR]

Enzymatic synthesis of enantiopure chiral halogenated aryl alcohols by ketoreductases (KREDs) is emerging but still challenging, due to the low solubility and slow mass transfer in aqueous media. As an ecofriendly tool for this issue, amphiphilic micelles are attractive. Herein, KRED-catalyzed reduction of halogenated aryl ketones in a TPGS-750-M formed aqueous micellar solution was conducted, achieving the corresponding chiral alcohols with moderate to excellent yields of up to 99% and remarkable enantioselectivities of >99% ee under the optimal conditions. Notably, the performance strengthening mechanisms of micelles in this process are illustrated, in which the solubilization position of the substrate plays an essential role and the substrates solubilized in the palisade layer of the micelles exhibit the highest increases in conversion and enantioselectivity. These findings provide guidance for rational design of enzyme catalysis in aqueous micellar media. [ABSTRACT FROM AUTHOR]

Sonogashira coupling is one of the cornerstone Palladium mediated cross coupling reactions, giving a direct and high yield access to symmetric and non‐symmetric alkynes with high tolerance of substituents. The method generally requires the use of CuI as a cocatalyst, an inert atmosphere to protect palladium catalyst, somewhat harsh conditions like prolonged heating and the use of organic solvents due to the hydrophobicity of reagents and products. Leveraging on the opportunities offered by micellar catalysis, we here present a general methodology to perform Sonogashira coupling in water, with moderate or no heating, under air, without copper co‐catalysts and at very low catalyst loading. The method offers the same generality and scope of organic solvents based couplings, but strongly improves sustainability while offering excellent yields. [ABSTRACT FROM AUTHOR]

This paper presents the first integrated techno-economic and life cycle assessment of microemulsion systems being applied for rhodium-catalyzed hydroformylation of long-chain alkenes at industrial scale. The case study describes a projected 150 kt/a production of tridecanal (US gulf coast, 2019). The industrial success of the hydroformylation of short-chain alkenes lies in the continuous recycling of the rhodium-containing water phase. Microemulsion systems can be applied to transfer this concept to long-chain alkenes by overcoming the miscibility gap between the aqueous catalyst phase and the unipolar alkene phase and, moreover, by generating a temperature-induced multi-phase system enabling the immobilization of the catalyst and its continuous recycling, as demonstrated in miniplant operations with dodecene and rhodium/SulfoXantPhos. Customizable simulation models have been developed for scale-up and assessment of the miniplant data. Surprisingly, a profitability-driven sensitivity study indicates a base case optimum at low residence time with low alkene conversion leading to large throughput streams and high raw material purge rates. The comparison to the industrial cobalt-based benchmark system shows an economic advantage regarding net present value (Rh: 68 M$; Co: 62 M$), while about half of the environmental indicators are in favor or equivalent. In a best-case scenario considering zero leaching of expensive rhodium the net present value increases by almost 40% accompanied by a shift to overall lower environmental impacts than the benchmark. In conclusion, the investigated miniplant data suggest microemulsion systems to be competitive when applied in continuous processes at a large scale. [ABSTRACT FROM AUTHOR]

A protocol has been developed that not only simplifies the preparation of nanoparticles (NPs) containing ppm levels of ligated palladium that affect heterogeneous catalysis but also ensures that they afford products of cross-couplings reproducibly due to the freshly prepared nature of each reagent. Four different types of couplings are studied: Suzuki-Miyaura, Sonogashira, Mizoroki-Heck, and Negishi reactions, all performed under mild aqueous micellar conditions. The simplified process relies on the initial formation of stable, storable Pd- and ligand-free NPs, to which is then added the appropriate amount of Pd(OAc)2 and ligand-matched to the desired type of coupling, in water.

DNA‐encoded libraries (DELs) have become a leading technology for hit identification in drug discovery projects as large, diverse libraries can be generated. DELs are commonly synthesised via split‐and‐pool methodology; thus, chemical transformations utilised must be highly efficient, proceeding with high conversions. Reactions performed in DEL synthesis also require a broad substrate scope to produce diverse, drug‐like libraries. Many pharmaceutical compounds incorporate multiple C−N bonds, over a quarter of which are synthesised via reductive aminations. However, few on‐DNA reductive amination procedures have been developed. Herein is reported the application of the micelle‐forming surfactant, TPGS‐750‐M, to the on‐DNA reductive amination of DNA‐conjugated amines, yielding highly efficient conversions with a broad range of aldehydes, including medicinally relevant heterocyclic and aliphatic substrates. The procedure is compatible with DNA amplification and sequencing, demonstrating its applicability to DEL synthesis. [ABSTRACT FROM AUTHOR]

Copolymers of styrene with a surface-active monomer 11-acryloyloxyundecyltrimethylammonium bromide were synthesized by free radical polymerization in water and thoroughly investigated by molecular hydrodynamic techniques i.e. analytical ultracentrifugation, dynamic light scattering, viscometry. Investigations, besides in depth macromolecular analysis, focus on studying the accelerating effect of the model reaction of alkaline hydrolysis para-nitrophenyl butyrate and resolving how solubilization capacity depends on the composition of the copolymers. [ABSTRACT FROM AUTHOR]

Molecular Dynamics (MD) simulations constitute a powerful tool that provides a 3D perspective of the dynamical behavior of chemical systems. Herein the first MD study of the dynamics of a catalytic organometallic system, in micellar media, is presented. The challenging methane catalytic functionalization into ethyl propionate through a silver‐catalyzed process has been targeted as the case study. The intimate nature of the micelles formed with the surfactants sodium dodecylsulfate (SDS) and potassium perfluorooctane sulfonate (PFOS) has been ascertained, as well as the relative distribution of the main actors in this transformation, namely methane, the diazo reagent and the silver catalyst, the latter in two different forms: the initial compound and a silver‐carbene intermediate. Catalyst deactivation occurs with halide containing surfactants dodecyltrimethylammonium chloride (DTAC) and Triton X‐100. Computed simulations allow explaining the experimental results, indicating that micelles behave differently regarding the degree of accumulation and the local distribution of the reactants and their effect in the molecular collisions leading to net reaction. [ABSTRACT FROM AUTHOR]

The hydrolytic decomposition of the organophosphorus ecotoxicant paraoxon in alkaline micellar solutions of a cationic surfactant with a carbamate fragment (CB-2-16) has been investigated by means of spectrophotometry. The stronger catalytic effect of micellar solutions aged during several days in comparison with freshly prepared ones has been associated with alkaline hydrolysis of the carbamate surfactant and the formation of a mixed system of CB-2-16 with its decomposition product cetyl(2-hydroxyethyl)dimethylammonium bromide (1H NMR spectroscopy data). In the absence of alkali, the decomposition products of the carbamate surfactant have not been detected for more than four months, indicating its hydrolytic stability in a neutral environment. [ABSTRACT FROM AUTHOR]

The micellar effects in the perhydrolysis and base-catalyzed hydrolysis of 4-nitrophenyl esters of phosphoric, phosphonic, and toluenesulfonic acids in organized microheterogeneous systems based on dicationic [Gemini surfactant AlkIm+–(CH2)3–Im+Alk∙2Br–, where Alk = C12H25 or C14H29 (GS)] and monocationic (AlkIm+CH3∙Br–, where Alk=C12H25 or C14H29) surfactants have been analyzed. The reagent concentrations have been found to be the main factor responsible for micellar catalysis. The hydroperoxide α-effect defined as the ratio of the second-order rate constants of perhydrolysis and base-catalyzed hydrolysis is preserved and, depending on the nature of the surfactant and the substrate, may reach ~ 100. [ABSTRACT FROM AUTHOR]

The micellar effects in the perhydrolysis and base-catalyzed hydrolysis of 4-nitrophenyl esters of phosphoric, phosphonic, and toluenesulfonic acids in organized microheterogeneous systems based on dicationic [Gemini surfactant AlkIm+–(CH2)3–Im+Alk∙2Br–, where Alk = C12H25 or C14H29 (GS)] and monocationic (AlkIm+CH3∙Br–, where Alk=C12H25 or C14H29) surfactants have been analyzed. The reagent concentrations have been found to be the main factor responsible for micellar catalysis. The hydroperoxide α-effect defined as the ratio of the second-order rate constants of perhydrolysis and base-catalyzed hydrolysis is preserved and, depending on the nature of the surfactant and the substrate, may reach ~ 100. [ABSTRACT FROM AUTHOR]

Organic synthesis, both in the laboratory and in industry, usually involves the use of a variety of solvents, the choice of which is determined by the nature of the reaction and its substrates. Water rarely enters the range of solvents for organic reactions. The problem is the solubility of organic substances in water. Micellar catalysis, based on the phenomenon of solubilization and local concentrating, provides the possibility of carrying out reactions of hydrophobic substances in water. This work demonstrates the effectiveness of using polymeric surfactants for the implementation in water of Suzuki cross-coupling, which is one of the most important constructive reactions in organic chemistry. [ABSTRACT FROM AUTHOR]

Organophosphorus compounds containing hydrolytically and metabolically stable C(sp3)– and C(sp2)–P bonds are widely used as reagents, ligands, pesticides, herbicides, flame retardants, surface modifiers, and antiviral and anticancer drugs. These applications rely on efficient C(sp3)– and C(sp2)–P bond-forming reactions. However, currently available C(sp2)–P cross-coupling protocols require high catalyst loadings and temperatures, as well as environmentally unsustainable and harmful organic solvents (e.g., N,N-dimethylformamide, DMF). Herein, we disclose a conceptually novel strategy for performing multimetallic Pd/Ni- and dual-ligand Pd-catalyzed C(sp2)–P cross-coupling reactions in aqueous micelles under mild and environmentally friendly conditions. Micellar catalysis in water enables C(sp2)–P cross-coupling while avoiding environmentally unsustainable organic solvents, thereby reducing organic waste generation. Such micellar C(sp2)–P cross-coupling reactions tolerate various functional groups and provide access to structurally diverse (hetero)aryl (thio)phosphonates, phosphinates and phosphine oxides using inexpensive commercial materials and catalysts. Moreover, C(sp2)–P cross-coupling reactions of medically relevant substrates and drugs under late-stage functionalization settings and multistep one-pot processes highlight the potential applications of this experimental paradigm. [ABSTRACT FROM AUTHOR]

Metallosurfactants, defined here as hydrophobic metal-containing groups embedded in hydrophilic units when dispersed in water, emanate in the formation of metallomicelles. This approach continues to attract great interest for its ability to serve as micellar catalysts for various metal-mediated chemical transformations in water. Indeed, relevant to green chemistry, micellar catalysis plays a preeminent function as a replacement for organic solvents in a variety of chemical reactions. There are several methods for the interaction of metal complexes (catalysts or catalyst precursors) and surfactants for producing micellar aggregates. A very effective manner for achieving this involves the direct bonding of the metal center to the amphiphilic polymeric materials. Herein, we describe the synthesis of a metallosurfactant containing a palladium complex covalently incorporated into a CO2-based triblock polycarbonate derived using a dicarboxylic acid chain-transfer agent. This amphiphilic polycarbonate was shown to self-assemble in water to provide uniform and spherical micelles, where the catalytic metal center is located in the hydrophobic portion of the micelle. The resulting metallosurfactant was demonstrated to effectively catalyze carbon-carbon coupling reactions at very low catalyst loadings. [ABSTRACT FROM AUTHOR]

A scalable and environmentally benign protocol for a Suzuki–Miyaura cross‐coupling in water using vitamin E derived surfactant TPGS‐750‐M is reported. The protocol is the most simple and standard for such transformations under micellar catalysis that has been amply utilized within our own research and development portfolio over the last decade. The impact of the synthetic procedure is reenforced by green Process Mass Intensity and Total Carbon Release metrics. [ABSTRACT FROM AUTHOR]

The one-pot three-component synthesis of 3,4-Disubstituted isoxazole-5(4H)-ones has been developed using an aqueous micellar medium as a catalyst under milder reaction conditions. The reaction was completed by using 25 mol% of sodium lauryl sulfate in an aqueous medium at room temperature. The reaction employs a green solvent, an eco-friendly reagent, and a non-chromatographic method for purification. The present reaction tolerates several substituted aldehydes and has proved to be efficient along with excellent yield. Moreover, the micellar catalyst was recovered and reused several times without significantly losing its catalytic activity.

Anion‐π catalysis operates by stabilizing anionic transition states on π‐acidic aromatic surfaces. In anion‐(π)n‐π catalysis, π stacks add polarizability to strengthen interactions. In search of synthetic methods to extend π stacks beyond the limits of foldamers, the self‐assembly of micelles from amphiphilic naphthalenediimides (NDIs) is introduced. To interface substrates and catalysts, charge‐transfer complexes with dialkoxynaphthalenes (DANs), a classic in supramolecular chemistry, are installed. In π‐stacked micelles, the rates of bioinspired ether cyclizations exceed rates on monomers in organic solvents by far. This is particularly impressive considering that anion‐π catalysis in water has been elusive so far. Increasing rates with increasing π acidity of the micelles evince operational anion‐(π)n‐π catalysis. At maximal π acidity, autocatalytic behavior emerges. Dependence on position and order in confined micellar space promises access to emergent properties. Anion‐(π)n‐π catalytic micelles in water thus expand supramolecular systems catalysis accessible with anion‐π interactions with an inspiring topic of general interest and great perspectives. [ABSTRACT FROM AUTHOR]

The hydrolysis reactions of crystal violet (CV) and p‐nitrophenyl acetate (PNPA) by sodium hydroxide in cetyltrimethylammonium bromide (CTAB) micellar solution were studied in this work. Combined with the Boltzmann probability of ionic species in an electrostatic potential field, a model with a numerical scheme was developed based on the nonlinear Poisson−Boltzmann equation in the micelle‐cell consisting of the reactants and the surfactant. The numerical solution gives the ionic species distribution in the micelle phase and the radius of the micelle‐phase. The dielectric constant of the micelle‐phase varies in the range of 39.8−54.4. The second‐order reaction rate constants in the micelle‐phase were determined using the electrostatic and dipolar free energy models. For the basic hydrolysis of CV and PNPA, the overall second‐order rate constants are three to five times and 1.4 times greater than the corresponding values in water, respectively. The rate enhancement occurs due to the distribution of the reactive ionic species in the cell region and the enhancement of the Coulombic and dipolar interactions among the ionic and polar reactants. [ABSTRACT FROM AUTHOR]

DNA‐Encoded Libraries (DELs) are becoming widely established as a hit identification strategy for drug discovery campaigns. Their successful application relies on the availability and efficiency of the reactions that can be carried out on DNA. These reactions should proceed with high conversion to the desired product and have a broad substrate scope to synthesise chemically diverse and drug‐like DELs. The Sonogashira coupling provides a unique means of coupling an sp‐hybridized carbon centre to an aryl halide and methods to achieve this reaction on DNA are highly desirable. We report the application of our micellar technology for on‐DNA chemistry to the Sonogashira reaction. This method gives highly efficient conversions for the coupling of (hetero)aromatic and aliphatic alkynes to (hetero)aryl iodides and bromides allowing the preparation of highly diverse DELs. [ABSTRACT FROM AUTHOR]

This review links various areas of inorganic chemistry around the themes developed by our research group during the last four decades. It is firstly based on the electronic structure of iron sandwich complexes, showing how the metal electron count dictates their reactivities, with various applications (via C–H activation, C–C bond formation) as reducing and oxidizing agents, redox and electrocatalysts and precursors of dendrimers and catalyst templates through bursting reactions. Various electron-transfer processes and consequences are explored, including the influence of the redox state on the acidity of robust ligands and the possibility to iterate in situ C–H activation and C–C bond formation to build arene-cored dendrimers. Examples of how these dendrimers are functionalized are illustrated using the cross olefin metathesis reactions, with application to the synthesis of soft nanomaterials and biomaterials. Mixed and average valence complexes give rise to remarkable subsequent organometallic reactions, including the salt influence on these reactions. The stereo-electronic aspect of these mixed valencies is pointed out in star-shaped multi-ferrocenes with a frustration effect and other multi-organoiron systems, with the perspective of understanding electron-transfer processes among dendrimer redox sites involving electrostatic effects and application to redox sensing and polymer metallocene batteries. Dendritic redox sensing is summarized for biologically relevant anions such as ATP2− with supramolecular exoreceptor interactions at the dendrimer periphery in parallel with the seminal work on metallocene-derived endoreceptors by Beer's group. This aspect includes the design of the first metallodendrimers that have applications in both redox sensing and micellar catalysis with nanoparticles. These properties provide the opportunity to summarize the biomedical (mostly anticancer) applications of ferrocenes, dendrimers and dendritic ferrocenes in biomedicine (in particular the contribution from our group, but not only). Finally, the use of dendrimers as templates for catalysis is illustrated with numerous reactions including C–C bond formation, click reactions and H2 production reactions. [ABSTRACT FROM AUTHOR]

Many years ago, twelve principles were defined for carrying out chemical reactions and processes from a green chemistry perspective. It is everyone's endeavor to take these points into account as far as possible when developing new processes or improving existing ones. Especially in the field of organic synthesis, a new area of research has thus been established: micellar catalysis. This review article addresses the question of whether micellar catalysis is green chemistry by applying the twelve principles to micellar reaction media. The review shows that many reactions can be transferred from an organic solvent to a micellar medium, but that the surfactant also has a crucial role as a solubilizer. Thus, the reactions can be carried out in a much more environmentally friendly manner and with less risk. Moreover, surfactants are being reformulated in their design, synthesis, and degradation to add extra advantages to micellar catalysis to match all the twelve principles of green chemistry. [ABSTRACT FROM AUTHOR]

Micellar catalysis offers a green alternative method for catalytic transformations by the solubilization of hydrophobic organic compounds. Biosurfactants represent a sustainable alternative to synthetic surfactants due to their biodegradability, low toxicity, and production from renewable feedstocks. In this work, we demonstrated the applicability of biosurfactant rhamnolipids in various micellar cross couplings, and prepared special fluorinated conjugated systems, active pharmaceutical ingredient (API) building blocks and bioactive compounds. [ABSTRACT FROM AUTHOR]

The kinetics of alkaline hydrolysis of tris(1,10-phenanthroline)Fe(II) has been explored spectrophotometrically in the presence of cyclodextrins (CDs), quaternary amphiphile (CTAB), and their mixed systems. All kinetics run in pseudo-first order conditions with excess concentration of alkali at 298 K (± 0.1 K). The reaction rate accelerates in the presence of CTAB. However, in the presence of CDs, the observed rate constant decreases continuously and also the catalytic properties of amphiphile diminishes, indicating the inclusion of both tris(1,10-phenanthroline)Fe(II) and surfactant into the CD cavity in the hydrolysis reaction. The cavity size of γ-CD among all of the CDs favors the incorporation of both Fe(II) complex and CTAB, which significantly reduces the micellar surface catalysis of CTAB. The decreasing sequence of the rate in CTAB-CDs mixed systems is observed as γ-CD > β-CD > α-CD. All the experimental kinetic results have been well explained based on the pseudo-phase model (PP model) of micelles and CD-inhibited model of CD systems. The calculated theoretical rate constant values are well consistent with the experimental data. In the absence and presence of CTAB, the calculated values of equilibrium binding constant between Fe(phen)32+ and γ-CD ( K Fe (II) CD ) are 109.17 (±1.03) and 414.74 (±3.63) (L mol−1), respectively, which support the diminishing of the catalytic properties of CTAB in the presence of γ-CD in the hydrolysis reaction. The experimental results also corroborate that fact. Finally, the effect of temperature on the reaction rate has been observed and the thermodynamic activation parameters have been evaluated. The linear plot of standard activated enthalpy with standard activated entropy reveals an iso-kinetic relationship that confirms a common mechanism for the reaction in different environments. [ABSTRACT FROM AUTHOR]

Surfactants with an ester bond connecting the polar headgroup and the hydrophobic tail are common. They are easy to synthesize, they can often be made from natural raw materials and their biodegradation profile is generally good, partly due to lipase or esterase catalyzed breakdown of the ester bond in sewage plants. A labile ester bond in the molecule may cause problems, however. Surfactants are often formulated at relatively high pH and it is important that they remain intact for a given period of time. In this article we discuss alkaline hydrolysis of different types of ester‐based surfactants—cationic, anionic and nonionic—and also of surfactant mixtures. We show that the ester bond in a surfactant has a different hydrolysis pattern than ester bonds in non‐surface active uncharged molecules. Cationic ester‐based surfactants are hydrolyzed rapidly while anionic and also nonionic ester‐containing surfactants are relatively resistant to hydrolysis. [ABSTRACT FROM AUTHOR]

The influence of the structure of higher secondary linear amines (di-n-butylamine (DBA), di-n-octylamine (DOA)), amides (methacrylamide (MAA), acrylamide (AA)) and additives of surfactants of different nature on the synthesis of promising cationic monomers, higher N-(dialkylaminomethyl)(meth)acrylamides, via the Mannich reaction in two-phase water-organic systems was determined. At the initial equimolar ratio of DBA, formaldehyde, and MAA under mild conditions, a high yield of the target monomer (96%) is achieved, and the introduction of a surfactant leads to the initial acceleration of the reaction but does not almost increase the yield. This is due to the manifestation of the effect of "micellar autocatalysis" in the absence of surfactants, since the formed amphi-philic aminoamide has surfactant properties. When MAA is replaced by AA, the yield of the aminoamide monomer does not exceed 80% because of the side formation of secondary amine addition products to the C=C bonds of the starting or formed amide. When using DOA, the reaction does not proceed to an appreciable extent because of steric shielding of the reaction center in the aminomethylating intermediate. [ABSTRACT FROM AUTHOR]

Conjugated semiconducting polymers are key active materials for printable electronics, sensors and biosensors, organic photovoltaics, organic light emitting devices, and more. The research in the field developed very efficient materials and sound structure property relationships, thus making a case for a transition from laboratory to industrial environment. At this critical juncture, sustainability, and ease of scaling up are at least as important as performances, to the point that efficient materials on a lab scale could become unpractical for the industry. The development of more efficient synthetic protocols and the complete removal of all organic solvents from both the synthesis and the processing of semiconducting polymers can help tremendously to improve sustainability and reduce costs. It is shown that the use of an aqueous dispersion of the food grade surfactant lecithin as the medium, enables the synthesis and processing of the representative semiconducting alternating copolymer poly (9,9‐dioctylfluorene‐alt‐bithiophene) (PF8T2) in high yield and high quality and with transistor performances comparable with those obtained with reference materials synthetized and processed from volatile organic solvents. [ABSTRACT FROM AUTHOR]

The development of micellar catalysis offers a sustainable alternative to organic solvents, and represents an environmental milestone in organic synthesis. Here, the first Michael addition of masked acetaldehyde under neutral, cationic and anionic micellar catalysis is reported, affording the products in high yields and enantiomeric excess, despite the use of water as solvent.

Triton-X-100, a polyethylene glycol 4-(tert-octyl)phenyl ether, has been found to be an active micellar organic catalyst for the one-pot selective synthesis of arylmethyl-H-phosphinic acids in up to 65% yields by the direct phosphinylation of arylmethyl halides with red phosphorus in the KOH/H2O/toluene multiphase superbase system. The catalyst demonstrates a good recyclability. As a result, an expeditious method for the chemoselective synthesis of arylmethyl-H-phosphinic acids—versatile sought-after organophosphorus compounds—has been developed. The synthesis is implemented via direct alkylation/oxidation of red phosphorus with arylmethyl halides, promoted by superbase hydroxide anions using Triton-X-100 (a commercial off-the-shelf organic recyclable micellar catalyst). The reaction comprises the hydroxide anions-assisted disassembly of Pred 3D polymer molecules triggered by the separation from the potassium cation in ordinary crown-like micelles to produce polyphosphide anions in aqueous phase. Further, polyphosphide anions are alkylated with arylmethyl halides in organic phase in the presence of the catalytic Triton-X-100 reverse micelles and alkylated polyphosphide species undergo the double hydroxylation. The advantages of the strategy developed include chemoselectivity, benign and accessible starting reagents, catalyst recyclability, and facile one-pot implementation. [ABSTRACT FROM AUTHOR]

In the pursuit of an advanced micellar catalysis system, the reaction sites in micelles determine its catalytic performances. However, the intrinsic polarity gradient of micelles anchors the reactants in the fixed regions, leading to an unmet challenge to steer the reaction sites to the optimal ones. To overcome this limitation, a Förster resonance energy transfer (FRET) spectroscopic ruler is established to position the true sites of reactants in micellar catalysis by using tetraphenylethylene (TPE) in the aggregation‐induced emission (AIE) micelles as the FRET donor and Nile red as the FRET acceptor. Subsequently, the customizable TPE steric barriers in the AIE micelles are apt to mediate the reactants into the polar micellar surface, the semipolar palisade layer, or the nonpolar internal layer, achieving the corresponding catalytic efficiencies. Additionally, the universality of steric barrier‐steered reaction sites in micellar catalysis is further demonstrated by the simple incorporation of small nonpolar molecules into the commercially available surfactants. To the authors' knowledge, this is the first report on the design of steric barriers to steer the reaction sites in micellar catalysis. These findings open up attractive perspectives for the exploration of new classes of efficient micellar catalysis systems in a variety of reactions. [ABSTRACT FROM AUTHOR]

Solvents are the major source of chemical waste from synthetic chemistry labs. Growing attention to more environmentally friendly sustainable processes demands novel technologies to substitute toxic or hazardous solvents. If not always, sometimes, water can be a suitable substitute for organic solvents, if used appropriately. However, the sole use of water as a solvent remains non-practical due to its incompatibility with organic reagents. Nonetheless, over the past few years, new additives have been disclosed to achieve chemistry in water that also include aqueous micelles as nanoreactors. Although one cannot claim micellar catalysis to be a greener technology for every single transformation, it remains the sustainable or greener alternative for many reactions. Literature precedents support that micellar technology has much more potential than just as a reaction medium, i.e., the role of the amphiphile as a ligand obviating phosphine ligands in catalysis, the shielding effect of micelles to protect water-sensitive reaction intermediates in catalysis, and the compartmentalization effect. While compiling the powerful impact of micellar catalysis, this article highlights two diverse recent technologies: (i) the design and employment of the surfactant PS-750- M in selective catalysis; (ii) the use of the semisynthetic HPMC polymer to enable ultrafast reactions in water. [ABSTRACT FROM AUTHOR]

Herein we report the arylation of Tröger's base via the Suzuki cross‐coupling reaction through aqueous micellar catalysis. The developed reaction conditions enabled us to prepare a variety of different derivatives with Tröger's base skeleton, using a low catalytic loading of the readily available Pd(OAc)2 catalyst and under environmentally friendly aqueous conditions. [ABSTRACT FROM AUTHOR]

Abstract Conjugated semiconducting polymers are key active materials for printable electronics, sensors and biosensors, organic photovoltaics, organic light emitting devices, and more. The research in the field developed very efficient materials and sound structure property relationships, thus making a case for a transition from laboratory to industrial environment. At this critical juncture, sustainability, and ease of scaling up are at least as important as performances, to the point that efficient materials on a lab scale could become unpractical for the industry. The development of more efficient synthetic protocols and the complete removal of all organic solvents from both the synthesis and the processing of semiconducting polymers can help tremendously to improve sustainability and reduce costs. It is shown that the use of an aqueous dispersion of the food grade surfactant lecithin as the medium, enables the synthesis and processing of the representative semiconducting alternating copolymer poly (9,9‐dioctylfluorene‐alt‐bithiophene) (PF8T2) in high yield and high quality and with transistor performances comparable with those obtained with reference materials synthetized and processed from volatile organic solvents.

OxFA-processing of inedible cellulose is considered as a perspective way for the production of biogenic formic acid (FA) which appeared to be a promising source for sustainable energy. In our work, the one-pot hydrolysis-oxidation of cellulose to FA was studied in the presence of the micellar acidic catalysts based on Mo–V–P heteropoly acids [Cn-MIM]y/H3+x-yPMo12-xVx (n = 6, 10 and 16; x = 1, 2 and 4; y = 2–6). The influence of amount of V, substitution of H+ by [Cn-MIM] and the length of alkyl group Cn of the cation was revealed. The optimization of the reaction conditions was also performed. To our knowledge, heterogeneous catalysts of such a composition were applied in cellulose hydrolysis-oxidation to FA for the first time. In the presence of C10-MIM/HPMo11V catalyst, the optimal reaction conditions were determined: 10 g/L of cellulose, 1.25–10 g/L of catalyst, 5 MPa of gas mixture (O2/N2 - 20/80 vol/vol) and 170–180 °C. Decreasing the alkyl group length of Cn-MIM+ cation or V content into framework of heteropoly anion were revealed to rise up the yield of the target product. These correlations were caused by the following factors. First, the decreasing acidity of micellar catalysts. Senond, the change in distribution of electron density in heteropoly anion due to the interaction between hydrogen atoms of alkyl group of Cn-MIM cation and oxygen atom of heteropoly anion. Third, blocking of V active sites for reagents. Influence of acidity on catalytic properties of micellar catalysts was also revealed in the course of screening samples with the different degree of protons substitution by C16-MIM+. The reaction rate was demonstrated to rise with increasing degree of protons substitution by C16-MIM + cation in C16-MIM/HyPMo11V and C16-MIM/HyPMo8V4 samples. The yield of FA up to 45 mol% can be reached over micellar HPA catalysts studied.

Cetyl trimethyl ammonium bromide (CTAB) assisted Oxidation of hypoxanthine (HXAN), and xanthine (XAN) alkaloids by Mn(VII) occurred smoothly in presence of aqueous Bronsted acid (HClO4, H2SO4) media. The rate of oxidation of HXAN, XAN by Mn(VII) was enhanced due to an increase in [HClO4] / [H2SO4] in the presence of CTAB at a constant temperature. Reaction kinetics obeyed I-order in [Mn(VII)], [HXAN], or [XAN] at constant temperature and acid concentration in micellar (CTAB) conditions. In this present work, the acidity functions developed by Zucker-Hammett, Bunnett, and Bunnett-Olsen were used for analyzing rate enhancement, and the probable reaction mechanism that involves water moiety in the slow step has been proposed according to the criteria of Bunnett-Olsen. [ABSTRACT FROM AUTHOR]

Fluorescent derivatives attract the attention of researchers for their use as sensors, photocatalysts and for the creation of functional materials. In order to create amphiphilic fluorescent derivatives of calixarenes, a fluorescein derivative containing oligoethylene glycol and propargyl groups was obtained. The resulting fluorescein derivative was introduced into three different (thia)calix[4]arene azide derivatives. For all synthesized compounds, the luminescence quantum yields have been established in different solvents. Using UV-visible spectroscopy, dynamic light scattering, as well as transmission and confocal microscopy, aggregation of macrocycles was studied. It was evaluated that calixarene derivatives with alkyl substituents form spherical aggregates, while symmetrical tetrafluorescein-containing thiacalix[4]arene forms extended worm-like aggregates. The macrocycle containing tetradecyl fragments was found to be the most efficient in photoredox ipso-oxidation of phenylboronic acid. In addition, it was shown that in a number of different electron donors (NEt3, DABCO and iPr2EtN), the photoredox ipso-oxidation proceeds best with triethylamine. It has been shown that a low molecular weight surfactant Triton-X100 can also improve the photocatalytic abilities of an oligoethylene glycol fluorescein derivative, thus showing the importance of a combination of micellar and photoredox catalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] The underlying mechanism for increased reaction rates in micellar catalysis-based organic synthesis is a reduced entropy barrier for the reaction. A two-dimensional localization of reactants and catalyst in the surfactant micelle reduces the translational entropy of all components. The entropy is reduced less for the reaction intermediate than for the reactants, which leads to the lower barrier. Quantum chemistry, the COSMO-RS implicit solvent model and statistical thermodynamics were employed to predict the stability of a range of reactants, catalysts and intermediates in a series of surfactant micelles. The localized stability in the linker region between the lipophilic and hydrophilic regions and the resulting decrease in entropy were also calculated. The predicted reaction rates for the proposed mechanism show that the entropy reduction leads to a larger prefactor for the reaction. The resulting reaction rate can be significantly higher than conventional organic synthesis in an organic solvent even when the smaller reaction volume and lower reaction temperatures typically needed under micellar catalysis conditions are considered. The results are general across a wide range of types of reactions, reactants and catalysts and a selection of surfactants commonly used in organic synthesis, strongly supporting the hypothesis. [ABSTRACT FROM AUTHOR]

New technology is reported that enables Negishi couplings to be run under sustainable, far greener conditions. Thus, ppm Pd‐containing nanoparticles (NPs) have been developed that catalyze couplings in recyclable water under very mild conditions. These heterogeneous reactions involve loadings of Pd of typically only 2500 ppm (0.25 mol %). Highly functionalized aromatic and heteroaromatic bromides readily participate, including examples taken from the Merck Informer Library indicative of the functional group tolerance associated with these couplings. Direct comparisons with existing literature routes are made. Very low residual levels of Pd in newly formed products are to be expected, as determined by ICP‐MS. The reagent involved has been extensively characterized via DLS, TEM, cryo‐TEM, and EDX measurements. [ABSTRACT FROM AUTHOR]

Fifteen gold(I)‐NHC‐functionalized amphiphilic block copolymers that differ in the type of linker (ethyl, pentyl, octyl and benzyl) that attaches the gold(I) NHC catalyst to the block copolymer backbone, as well as, the substitution pattern of the NHC ligand (i. e. mesityl, methyl, 2,6‐diisopropylphenyl and n‐hexyl) were synthesized by a reversible addition and fragmentation transfer (RAFT) polymerization process. Micelle formation of the gold(I) NHC polymers was analyzed by electron microscopy and dynamic light scattering and revealed spherical and rod‐like particles from 12 to 96 nm. In the micellar, gold(I) catalyzed cycloisomerization of an allene to the corresponding dihydrofuran, linker flexibility and substitution pattern of the NHC‐ligand showed a strong effect on the catalytic activity. Best results were obtained were obtained for gold(I) NHC catalysts bound to the polymer backbone by pentyl linker whereas the rather stiff benzyl linker gave lowest catalyst conversion. Moreover, the polymer catalyst could be recycled in four consecutive runs and gave activities from 35 to 84 % in the fourth run and underscores the importance of fine tuning structural parameters to achieve high conversion under micellar reaction conditions. [ABSTRACT FROM AUTHOR]

A sustainable and ultrafast protocol was developed for the N-arylation of sulfoximines with aryl bromides in water. The protocol requires low catalyst loading and the synthesis period was shortened to several minutes. The strategy was compatible with diverse aryl bromides and sulfoximines, giving scaffolds in good to excellent yields. [ABSTRACT FROM AUTHOR]

Many years ago, twelve principles were defined for carrying out chemical reactions and processes from a green chemistry perspective. It is everyone’s endeavor to take these points into account as far as possible when developing new processes or improving existing ones. Especially in the field of organic synthesis, a new area of research has thus been established: micellar catalysis. This review article addresses the question of whether micellar catalysis is green chemistry by applying the twelve principles to micellar reaction media. The review shows that many reactions can be transferred from an organic solvent to a micellar medium, but that the surfactant also has a crucial role as a solubilizer. Thus, the reactions can be carried out in a much more environmentally friendly manner and with less risk. Moreover, surfactants are being reformulated in their design, synthesis, and degradation to add extra advantages to micellar catalysis to match all the twelve principles of green chemistry.

Ethyl diazoacetate (EDA), which is easily prepared from ethyl glycinate and NaNO2, reacts in situ with alkynes in a water micelle environment without organic solvent to form pyrazoles. The reaction is pH dependent, as in the presence of protic catalysis (H2SO4 4 %, pH 3.5) a mixture of 3,5‐ and 4,5‐disubstituted pyrazoles was obtained, while, at pH 5.5, only the 3,5‐disubstituted isomer was obtained. The presence of the surfactant TPGS‐750‐M was crucial to secure clean crude reaction mixtures and high yields of the products. The same protocol was successfully applied to the synthesis of substituted pyrazolines. [ABSTRACT FROM AUTHOR]

Kinetics of the reaction of maltose with cerium ammonium sulfate were analyzed spectrophotometrically by observing the decrease of the absorbance of cerium (IV) at 385 nm in the presence and absence of polyethylene glycols (600, 1500, and 4000) and polyvinylpyrrolidone (PVP), in addition to anionic micelles of sodium dodecyl sulfate (SDS), cationic micelles of cetyltrimethylammonium bromide (CTAB) and non-ionic micelles of Tween 20 surfactants. Generally, there is little literature about using the polymers (PEGs and PVP) as catalysts in the oxidation-reduction reactions. Therefore, the major target of this work was to investigate the influence of the nature of polymers and surfactants on the oxidation rates of maltose by cerium (IV) in acidic aqueous media, as well as employing the Piszkiewicz model to explain the catalytic effect. The kinetic runs were derived by adaptation of the pseudo first-order reaction conditions with respect to the cerium (IV). The reaction was found to be first-order with respect to the oxidant and fractional-order to maltose and H2SO4. The reaction rates were enhanced in the presence of polymer and micellar catalysis. Indeed, the surfactants were found to work perfectly close to their critical micelle concentrations (CMC). Electrostatic interaction and H-bonding appear to play an influential role in binding maltose molecules to polymer/surfactant micelles, while oxidant ions remain at the periphery of the Stern layer within the micelle. [ABSTRACT FROM AUTHOR]

The kinetics of anionic, cationic, neutral surfactant and catalyzed Fe(III) polypyridyl complex were studied. The kinetics of Fe(NN)33+ oxidation of amino acids was followed spectrophotometrically in the presence and absence of surfactants, and also the values of the binding constant, of different sulfur-containing amino acids with surfactants, were determined. The redox reaction has been carried out in an aqueous medium, and the addition of acetonitrile facilitates the reaction initially. Electron transfer (ET) mechanism for the Fe(NN)33+ oxidation of amino acids containing thiol and thioether moiety is studied. The kinetic data obtained for the reaction in the presence of different concentrations of SDS, CTAB and Triton x-100 for Fe(NN)33+ oxidation of several amino acids are collected. In the presence of SDS, the sulfate head group can stabilize sulfide cation of the transition state in the ET reaction of Fe(NN)33+ with sulfide formed due to ET from sulfide to Fe(NN)33+. Among the thiol-containing amino acids, glutathione shows more pronounced catalysis. Compared to Fe(bpy)33+, the reaction of Fe(phen)33+ with sulfur-containing amino acids is favored in SDS. ET reaction of [Fe(NN)3]3+ with sulfur-containing amino acids is in the presence of CTAB and nonionic surfactant, Triton-x also studied. [ABSTRACT FROM AUTHOR]

Replacement of organic solvents, in particular chlorinated, aromatic, and polar aprotic ones, is an emerging issue that can find a solution in the development of catalytic reactions in water. Nature performs a multitude of chemical transformations in water under mild conditions mediated by enzymes. In particular the nanoconfinement effects of the enzymes ensure high activity and impressive stereoselectivities. Micellar catalysis is nowadays a real alternative approach to catalysis in traditional organic media, enabling good activity under mild conditions, with the advantage of possible catalyst and micellar medium recycling. Micellar media emerged also as good nano‐environments for stereoselective reactions, with many examples of chemical transformations mediated by metal and organo‐catalysts for which improvements of stereoselectivity were observed with respect to the same reaction under homogeneous conditions in traditional organic solvents. More specifically, both the catalytically active site and the micelles provided by the surfactant can contribute to the asymmetric induction, partially resembling what known in terms of stereoselectivity imparted by the active site of enzymes and metallo‐enzymes. [ABSTRACT FROM AUTHOR]

The influence of humic aggregates in a water solution upon the chemical stability under basic conditions of different substrates was reviewed. The kinetic behavior of each substrate was modeled in terms of a micellar pseudophase model. [ABSTRACT FROM AUTHOR]