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Highly stable iPrOH/H2O (4:1) suspensions of few-layer antimonene (FL-Sb) are prepared by liquid-phase exfoliation of ground Sb crystals via sonication without the need for surfactants (400 W, 24 kHz, 40 min).

The building blocks of the well-defined and easily modified carbon-bond structure of graphene sheet units bring unique characteristics to carbon materials. Especially when these carbon materials are nanosized, their tunable electronic states, giant conjugated structures, oxygen groups on the defects of graphene sheets, and various dopants all help make the materials active in liquid-phase catalytic reactions. In this mini-review, we mainly focus on the liquid-phase reactions catalyzed by carbon nanomaterials, and the related mechanisms are discussed on the basis of their structure fundamentals. In the final section, we also provide our perspectives on this rapidly developing carbocatalysis field.

Solution-phase catalysis using molecular transition metal complexes is an extremely powerful tool for chemical synthesis and a key technology for sustainable manufacturing. However, as the reaction complexity and thermal sensitivity of the catalytic system increase, engineering challenges associated with product separation and catalyst recovery can override the value of the product. This persistent downstream issue often renders industrial exploitation of homogeneous catalysis uneconomical despite impressive batch performance of the catalyst. In this regard, continuous-flow systems that allow steady-state homogeneous turnover in a stationary liquid phase while at the same time effecting integrated product separation at mild process temperatures represent a particularly attractive scenario. While continuous-flow processing is a standard procedure for large volume manufacturing, capitalizing on its potential in the realm of the molecular complexity of organic synthesis is still an emerging area that requires innovative solutions. Here we highlight some recent developments which have succeeded in realizing such systems by the combination of near- and supercritical fluids with homogeneous catalysts in supported liquid phases. The cases discussed exemplify how all three levels of continuous-flow homogeneous catalysis (catalyst system, separation strategy, process scheme) must be matched to locate viable process conditions.

Nitrobenzenes are reduced to the corresponding anilines with nearly full conversion and excellent selectivities while reduction-sensitive substituents (e.

Sulfide solid electrolytes with cubic Na3PS4 phase were firstly synthesized via a liquid-phase process. A yellow solution was obtained after the reaction of Na2S and P2S5 in N-methylformamide (NMF)...

The heterogeneous title reaction exhibits superior activity compared to homogeneous cobalt phthalocyanine catalysts with added benefits of easy recovery and recycling.

Reduction reactions play significant roles in industrial manufacture, and supported metal nanoparticles (NPs) show great prospect for mass production. The gold NPs have achieved expanding progress in selective reduction in recent years and will lead to a hot issue in the future. However, the designing of efficient catalysts is currently quite challenging because of the lack of systematic understandings on the fundamentals of the catalytic efficiency. Fortunately, tremendous advances can be expected with the aid of quasi-homogeneous NPs. This review highlights the unsupported gold NPs or nanoclusters (NCs) catalyzed reduction reactions, which include single-electron-transfer catalysis, selective hydrogenation of carbonyl and nitro groups. The tentative catalytic mechanism and the size-dependence of gold nanocatalyst have also been discussed in this review.

Newly synthesized dioxidomolybdenum(VI) complexes are tested for the oxidation of secondary alcohols (I) using conventional liquid phase and microwave-assisted method with 30% aqueous H2O2 as oxidant giving the respective ketones (II).

Due to their unprecedented intrinsic structural features, like tunable pore diameter of nanoscale dimensions, huge BET surface areas and good flexibility to recognize/accommodate various functional groups and metals onto the surface, an inevitable linkage of nanoporous materials with catalysis has been built-up over the past few decades. As a result of which, a huge number of communications and articles dealing with these materials with nanoscale porosity have come to light. In this review, our objective is to provide a comprehensive overview of mesoporous solids, the most remarkable member of the nanoporous family of materials, the general strategy for their syntheses and application of functionalized porous materials in liquid phase catalytic reactions. In the latter part, the role of catalytic centres in various organic transformations over these functionalized mesoporous materials and their economical, environmental and industrial aspects are described in detail.

The partial hydrogenation of benzene to cyclohexene is an economically interesting and technically challenging reaction. Over the last four decades, a lot of work has been dedicated to the development of an exploitable process and several approaches have been investigated. However, environmental constraints often represent a limit to their industrial application, making further research in this field necessary. The goal of this review is to highlight the main findings of the different disciplines involved in understanding the governing principles of this reaction from a sustainable chemistry standpoint. Special emphasis is given to ruthenium-catalyzed liquid phase batch hydrogenation of benzene.

Nano-/hierarchical zeolites have received increasing attention due to their catalytic performance preferable to that of conventional zeolites. The two major textural features of nano-/hierarchical zeolites, i.e. short microporous channel and large external surface area, can provide them with high activity and lifetime as well as high selectivity for products during catalysis. This perspective focuses on the most representative behavior of nano-/hierarchical zeolites in gaseous phase and liquid phase catalytic systems, considering whether the reaction is predominantly catalyzed within the micropore or at the external surface, and whether it is shape-selective. The catalytic characteristics and future prospects of nano-/hierarchical zeolites are highlighted in their applications in gaseous and liquid phase reactions.

Polyoxometalates (POMs) are a unique class of molecular metal oxides with a tunable structure at the atomic level. They have demonstrated various potential applications in various fields. In particular, POMs have been widely used as catalysts, due to their facilely modified acid–base properties and redox potential through molecular designing. Normally, POMs can be utilized as both homogeneous and heterogeneous catalysts, where the former favors high activity, while the latter benefits facile separation of the catalysts. Faced with the requirement for sustainable development, significant effort has been made in the preparation of POM-based heterogeneous catalysts. This review focuses on the recent developments in heterogeneous strategies of POM-based catalysts and their applications in liquid organic reactions.

All experimental data on phase equilibria and thermodynamic properties of the Co–Nd, Cu–Nd and Nd–Ni binary systems in literature were reviewed and critically examined. A set of optimized model parameters for all solid stoichiometric compounds and liquid phase was built to reproduce all available reliable thermodynamic properties and phase diagram data within experimental error limits. The Modified Quasichemical Model in the pair approximation was used to describe the thermodynamic properties of the liquid solution accurately. Systematic changes in the phase diagrams and thermodynamic properties between Nd–X binary systems, where X=Mn, Fe, Co, Ni and Cu, are presented and discussed.

An efficient, clean, eco-friendly, and simple method for the title reaction by employing H3PW12O40 as catalyst is developed.

Long (

LnSe2 nanosheets (Ln: La—Nd; nanobars for EuSe2) and Ln4O4Se3 nanoplates (Ln: Nd, Sm, Gd—Ho) are prepared from mixtures of Ln(acac)3 (Ln: La, Pr, Nd, Sm—Ho) or Ce(OAc)3, excess SeO2, oleic acid, oleylamine, and 1-octadecene (310—320 °C, 30—60 min).

Leached phase-separated porous glasses are interesting support materials for heterogeneous catalysts utilized for cross-coupling reactions and hydrogenation reactions in the liquid phase. The option to construct tailor-made porous structures and shapes of the particles results in materials with interesting properties for catalysis, such as narrow pore size distribution or specific surface area. Loading of porous glasses with various metals by the wet-impregnation technique leads to active catalysts for widespread applications in organic synthesis. This article reviews the application of porous glass-based catalysts for the construction of new C-C bonds as well as for chemoselective hydrogenation under microwave-assisted or classical heating conditions.

The perovskite BiNb3O9 is a metastable phase in the Bi2O3—Nb2O5 system that forms only when cooled from a liquid phase.

We report on the synthesis, characterization and catalytic performance of new, supported Pd-II and Pd-0 catalysts. The catalysts are characterized by TEM, XRD, FTIR, X-ray photoelectron spectroscopy, and vibrating sample magnetometry. The catalysts are found to be active in both forms, Pd-II and Pd-0, for the carbonylative cross-coupling reaction of aryl iodides with arylboronic acids, and for the hydrogenation of aromatic nitroand unsaturated compounds. The newly developed catalysts are prepared by a synthetic strategy that is similar to the one used for other supported catalysts but are easier to recover- they can be recycled by magnetic separation from liquid phase reactions-and can be used for at least 5 consecutive trials without any decrease in activity.

The advantages and disadvantages of existing approaches to the synthesis of oligodeoxyribonucleotides (ODN) are discussed focusing on large-scale methods. The liquid phase and solid supported synthesis and the synthesis on soluble polymers are discussed. Different problems concerning the methods and implementation of the ODN synthesis are outlined depending on goals of using target oligomers.

A series of Pd-incorporated titanate catalysts are synthesized by intercalation of Pd(NO3)2 into layered potassium titanate, which proceeds via a cation-exchange reaction in molten phase.

Hydroxyhalogenation of cyclic dienes using a combination of hydrogen/metal halides and H2O2 gives halohydrin derivatives, which suffer dehydrohalogenation on treatment with powdered KOH to furnish corresponding diepoxy derivatives [cf.

Ionic liquids (ILs) which are made up of cationic and anionic components can be designed to possess a definite set of properties. In this context, the term “designer solvents” has been used to demonstrate the potential of these environment-friendly ionic liquids in chemical reactions. Since these liquids are able to dissolve several transition metal complexes, they have often been employed in recent times in several catalytic reactions to enhance reaction rates and selectivities. The concept of “immobilized” liquids has been derived from supported liquid phase catalysts; the immobilization process transferring the desired catalytic properties of the liquids to solid catalysts could combine the advantages of ILs with those of heterogeneous support materials and various catalytically functional groups or active species. The immobilized functional ionic liquids (IFILs) capable to restrict many of the negative effects of the conventional ILs have successfully been used in various potent catalytic areas affording high catalytic activity. In this review, structural characteristics, properties and preparation of immobilized functional ionic liquids have been described and the results are compared with those of traditional ILs. Special emphasis has been paid to comprehend the mechanism of various catalytic processes using immobilized ionic liquids functionalized by different groups.

A wide range of methylarenes and methylheteroarenes are selectively converted into the corresponding primary monoamides and nitriles even in the case of methylarenes bearing two or more methyl groups.

In the swim: until now, X-ray photoelectron spectroscopy (XPS) has been predominantly applied to the investigation of near-surface regions. Recent work has now brought XPS into a new domain with the direct monitoring of bulk reactions in the liquid phase. In the monitored reaction, the cation of an ionic liquid (IL) reacts with the anion of another IL.

The nanoporous Au-catalyst, obtained by dealloying of Au30Ag70 alloy thin films with HNO3, is reusable multiple times without leaching and loss of activity.

The title phosphor is synthesized by conventional solid state reaction, a new liquid phase precursor approach using SiO2 sol, and a liquid phase precursor approach using a water-soluble silicon compound (obtained from Si(OEt)4, propylene glycol, and HCl at 80 °C for 48 h).

Over the past twenty years there has been intense interest in the design and understanding of catalysis by gold. More recently, it has been observed that alloying gold with a second metal greatly enhances the catalytic efficacy. These supported nanoparticles offer great potential as catalysts for the synthesis of fine chemicals and they are now at the stage where they can contribute to the sustainable development of chemical processes, in particular selective oxidation. A number of factors have contributed to this increased interest; namely, environmental issues promoting the need for more atom efficient processes and the new advances in the synthesis of nanoparticles as well as the characterisation methods available for their study. New catalytic materials obtained by careful control of the morphology of the metal nanoparticles and their use under solvent-free conditions all contribute to the latest developments. Most importantly their use can obviate the need to use stoichiometric oxidants. In this perspective we demonstrate the recent advances in these materials for selective oxidation reactions.

Data on the factors affecting the result of laser-induced chemical liquid phase deposition of metals, first of all copper, are generalized and described systematically. The attention is focused on the chemical reactions in solution and activation of dielectric surfaces. The mechanisms of chemical and laser-induced deposition of local copper structures from solution onto dielectric surface are considered. The effect of the solution components on the result of deposition is discussed. The bibliography includes 92 references.

Metal organic frameworks (MOFs) are crystalline porous materials constituted by the coordination of metal ions or clusters of metal ions with bipodal or multipodal rigid linkers. Due to the high metal content, large surface area, and porosity, these materials have attracted a considerable attention as solid catalysts of organic reactions in the liquid phase. In the present chapter, we first describe the main features of MOFs that make these materials very appropriate as catalysts and, then, describe briefly the use of MOFs as catalysts for organic reaction types. The final part summarizes the state of the art in the use of MOFs as catalyst and describes our view on future developments in the field.

Heterogenization methods of homogeneous catalytic systems to render the catalyst and the product(s) in separable phases to allow facile separation are summarized. The applications of two liquid phases with no, limited, or temperature regulated miscibility of the two phases or a solid phase and a liquid phase with no, limited, or temperature regulated solubility of the constituent(s) of the solid phase in the liquid phase are demonstrated on selected examples.

The microstructure (composition, size and shape etc.) of semiconductor nanocrystals determine the electronic density of states of semiconductor nanomaterials and ultimately determine their optical and electrical properties. Semiconductor nanocrystal advanced structures, such as hybrid nanostructures and nanocrystal superlattices, not only integrate the function of individual nanocrystals, but also brings the materials collective and synchronic properties. How to control the monodispersity, composition and structure of as-prepared semiconductor nanocrystals during their syntheses, as well as their furthermore assembly, has been a hot research area in this decade. This critical review focuses on the development of synthetic and assembly methods (techniques) of semiconductor nanocrystals processed in the liquid phase. Emphasis is on the synthesis methodology, microstructure related properties of semiconductor nanocrystals, and their applications (243 references).

Review: overview of existing methods, benefits of catalytic hydrodechlorination (HDC) over separation/oxidation methods, detailed considerations of liquid phase HDC of chlorophenols over Al supported Pd and gas phase conversion of halogenated aromatics over silica supported Ni; 321 refs.

5-Hydroxymethylfurfural (HMF) was converted to maleic anhydride in 52% yield via selective oxidation with molecular oxygen using VO(acac)2 as catalyst in liquid phase.

The new polyoxotungstate (IV) crystallizes in the triclinic space group P with Z = 1 (single crystal XRD).

An efficient method for the synthesis of aldehydes was achieved by using air-microbubble techniques in aerobic copper/TEMPO-catalyzed oxidation of primary alcohols. Use of air-microbubbles to improve gas absorption into liquid phase is proven to be highly beneficial for gas/liquid phase reactions.

The high degree of organisation in the fluid phase of room-temperature ionic liquids has major consequences on their macroscopic properties, namely on their behaviour as solvents. This nanoscale self-organisation is the result of an interplay between two types of interaction in the liquid phase – Coulomb and van der Waals – that eventually leads to the formation of medium-range structures and the recognition of some ionic liquids as composed of a high-charge density, cohesive network permeated by low-charge density regions.

Bimetallic nanocrystals (NCs) with core/shell, heterostructure, or inter-metallic and alloyed structures are emerging as more important materials than monometallic NCs. They are expected to display not only a combination of the properties associated with two distinct metals, but also new properties and capabilities due to a synergy between the two metals. More importantly, bimetallic NCs usually show composition-dependent surface structure and atomic segregation behavior, and therefore more interesting applied potentials in various fields including electronics, engineering, and catalysis. Compared with monometallic NCs, preparation of bimetallic NCs is much more complicated and difficult to be achieved. In recent years, researchers from many groups have made great efforts in this area. This review highlights the recent progress in the chemical synthesis of bimetallic NCs. The control over morphology, size, composition, and structure of bimetallic NCs as well as the exploration of their properties and applications are discussed.

Recent achievements in the preparation of polyoxometalate-based heterogeneous catalysts using different immobilization techniques, such as embedding into a silica matrix by sol–gel method, irreversible adsorption on active carbon, electrostatic attachment to NH2-modified mesoporous silica, and incorporation within nanocages of the metal-organic framework MIL-101 are surveyed. The catalyst characterization is reported, and their catalytic performances in liquid phase selective oxidations are compared, with special attention being paid to the questions of catalyst stability to leaching, nature of catalysis and catalytic properties after recycling. The scope and limitations of the POM-based heterogeneous catalysts are discussed.

Selective trifluoromethylation of the corresponding chlorinated compounds is achieved by successive Cl/F exchange under mild conditions using HF as the fluorinating agent.

Pentaerythritol turns out to be an efficient soluble tetrapodal support permitting the traceless release of various biaryl compounds attached by a sulfonate linkage.

The title nano- and microrods are synthesized by addition of HNO3 (nanorods) or H2SO4 (microrods) to solutions of (NH4)6Mo7O24 followed by supersonication for 50 min or heating at 60—100 °C for 20 min.

Rate constants for bimolecular reactions, obtained through time-resolved kinetic studies both in the gas and liquid phases are reviewed. Data for reactions of MeSiH, PhSiH, ClSiH, SiCl(2), SiMe(2), MeSiPh, SiPh(2) and SiMes(2) are covered. Where possible, substituent effects relative to SiH(2) have been obtained. These demonstrate widely varying effects between different types of reaction, which aids mechanistic understanding. Reactivities are high for all silylenes, but substituents can reduce them by both electronic and steric effects. The gas and liquid phase data (mainly for SiMe(2)) are compared and appear to be reasonably consistent. This review, although detailed, is not comprehensive.

For biorenewable feedstocks to serve as a significant source of chemicals and/or fuels, the development of new chemical processes as well as biological processes will be required. However, the conversion of biorenewable feedstocks with heterogeneous catalyst-based processes provides new challenges in inorganic catalyst research and development relative to historical work with petrochemical feedstocks. These catalyst and process challenges include the need to convert highly functionalized molecules with high selectivity, to develop stable catalytic liquid−solid interfaces in which the liquid phase is commonly aqueous, to control solvent phase effects and to develop novel reaction systems. While some of these challenges will be addressed using novel catalytic materials, others will need to be overcome through design of new catalytic reaction systems. Examples of emerging research results demonstrating unique approaches that have been taken to begin to address the efficient conversion of biorenewable feedsto...

A fast, general, environmentally friendly, and facile method for preparation of phenyl bis-esters under microwave irradiation in liquid phase is presented. Selective reaction pathways in order to get phenyl bis-esters only or phenyl monoesters only have been found. The microwave enhanced remarkably the rate of esterification, the reaction time decreasing dramatically, the reaction conditions were milder, the consumed energy decreased considerably and the amount of used solvents was reduced substantially. Consequently, the microwave-assisted esterification reaction could be considered eco-friendly. In the most cases, under MW irradiation the yields were higher than those in ordinary conditions, in some cases substantially (at least 75%). A feasible explanation for the MW efficiency is presented, ionic conduction mechanism having the higher contribution. A comparative study, microwave-conventional conditions was done.

In the first part of the review mention will be made of some recent developments in NMR techniques which are potentially important for future 2D-EXSY and 2D-NOESY studies of molecular motions. The second part of the review illustrates recent applications of NMR methods to studies of stereochemical non-rigidity in liquid phase inorganic and organic systems

2,6-Diisopropylnaphthalene is selectively produced in the liquid phase alkylation of naphthalene with propene or propan-2-ol over H-mordenite catalyst.