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Platinum (Pt) is used as a catalyst in most fuel cells, but the use of this metal is limited with the increasing advancement in fuel cell technology. Investigating the interaction between oxygen molecule (O2) and organometallic compounds as catalysts and their activation role for O2 is an interesting area of research worldwide. Some organometallic compounds have been used in this study as catalysts for the activation of O2 and CH4 in “oxygen–methane” fuel cell. Accordingly, the catalytic effect of CrC4H4 and CuC4H4 organometallic compounds on increasing the oxygen–methane fuel cell reaction efficiency was investigated using Density Functional Theory (DFT) by B3LYP/6 -31 G(d) method. The activation of O2 in the cathode and methane in the anode was investigated in CrC4H4/O2, CuC4H4/O2, CrC4H4/CH4, and CuC4H4/CH4 structures. The calculations revealed that the bond length increased by about 23 and 18% on average for O2 and 3 and 0.9% for C–H methane in response to the adsorption process in the presence of CrC4H4 and CuC4H4. This result could be due to the relative electron transfer from the organometallic compound to oxygen or to C–H methane. Thus, the desired organometallic compound activates the adsorbed oxygen molecule and the adsorbed methane to participate in the cell reaction.

1,2-Oxazines were synthesised via a copper-catalysed aerobic acyl nitroso Diels–Alder reaction from 1,4-disubstituted 1,3-dienes and N-Boc-hydroxylamine. From this, 1,2-oxazinanes were obtained in a novel follow-up reaction path. The stability of several 1,2-oxazines and 1,2-oxazinanes towards organometallic compounds was tested to rate their operability as cyclic chiral Weinreb amide auxiliaries. 3,6-Di-tert-butyl-1,2-oxazinane gave the best results and was introduced as a chiral Weinreb amide-type auxiliary to yield chiral α-substituted ketones in a diastereomeric ratio of up to 98:2. The removal of the auxiliary can be performed with BuLi to form unsymmetrical α-chiral ketones. Thereafter, the chiral auxiliary can be re-isolated and purified by sublimation under vacuum.

Recently published syntheses, reactions and characterizations of unusual unsaturated ring strained Group 4 metallocene metallacycles like metalla-cyclocumulenes, -cycloallenes and -cycloalkynes with different ring size are updated for the last three years. There exist for some of these metallacycles, depending on the ring size, 7-, 5- and 4-membered compounds. The new results for these metallacycles are summarized here and considered in addition to the former published results. Additionally, several compounds of this type were now characterized by new reactions. For a better understanding of these compounds, some spectroscopical methods as well as theoretical calculations were published. Despite of these all-C-metallacycles, only in some cases the syntheses and reactions for the corresponding hetero-metallacycles were published too. Examples for these metallaheterocyclic compounds will not be considered in this article. All these unusual ring strained compounds have a great potential for a lot of interesting synthetic applications in the future. Additionally, they are very interesting from the theoretical point of view.

The use of platinum metal (Pt) as a catalyst is common in fuel cells. Much research has been conducted to replace this precious metal for reducing the costs and time. This research studies the enhancing of the efficiency of methane-oxygen fuel cell using density functional theory at PW91 level and base series 6-31G (d) by replacing organometallic compounds as catalysts. The results of the calculations revealed that the interaction of organometallic compounds (TM-CmHm, TM = Cr, Mn, Sc, Ti, V, and m = 4, 5) with oxygen and methane plays a good catalytic role in this fuel cell. The presence of transition metal in alloying compounds caused the transfer of a small amount of negative electrical charge to the 2π* orbitals of O2 and CH4 molecules. Thus, the increase in bond length of O2 and CH4 molecules was significant, and this cell became more unstable as well as active to participate in half-reactions. Accordingly, it would participate in the cathodic and anodic half-reactions with higher speed and reactivity. Transition state calculations indicated that the reaction of these organometallic compounds was possible kinetically and thermodynamically. In general, the results of calculations showed that ScC5H5 has a higher catalytic role. Therefore, the bond lengths of O=O and C–H in O2 and CH4 molecules were increased by 24% and 22%, respectively. Thus, these organometallic compounds can be considered as effective, convenient, and inexpensive catalysts to increase the rate of reaction of methane-oxygen (CH4–O2) cells.

A novel electrosynthetic method has been introduced based on alternate layer-by-layered self-assembly of conjugated/unconjugated Salen-based nanowires as a capacitive pseudo-supercapacitor. For this purpose, a three-electrode system consisted of a glassy carbon (GC), Ag/AgCl (Sat’d Cl−) and a Pt rod as working, reference, and counter electrodes, respectively. The electrolyte included the same molar concentration (0.040 mol L−1) of each Salen monomer (as initial precursor), and KCl solution (as supporting electrolyte), besides using KOH solution (0.01 mol L−1, as basic-controlling reagent) inside acetone/water (4:1, V/V) as a solvent. The formation of this self-assembly nanowire was attributed to the control of the electrical conductivity of this polymer during formation of an organometallic complex with K+ as responsible complex forming agent. This novel nanowire then played role as a capacitive pseudo-supercapacitor. Based on the chrono—potentiometry, reproducible charge/discharge process for at least 5000 cycles was observed at a potential between − 2.00 and + 1.75 V (vs. Ag/AgCl). The capacity behavior of the polymer was also evidenced using electrochemical impedance spectroscopy. This synthesized polymeric nanowire was adopted as the acceptable pseudo-supercapacitor with real capacity equals to 3110 ± 6 (n = 3) C g−1. This study was considered as the first report at which the self—assembly of organometallic compounds as an efficient pseudo—supercapacitor was introduced.

The interesting areas of research is fuel cells, where the role of catalytic action in the cathode and anode is of interest. In this research, using density functional theory (DFT) and B3LYP/6-31G* method, the catalyst effect of TM–C4H4 (organometallic compounds) (TM = Zn, Cr) in oxygen–hydrazine (N2H4) fuel cell was examined. The transition metals in organometallic compounds influence the bond length of O2 in the cathode and N2H4 in the anode. Specifically, the bond length of O2 in the vicinity of TM-C4H4 increased by 23–25%, while the bond length of N=N in N2H4 increased by 1.5–3% on average. This bond length elevation is due to charge transfer to π*-orbitals of O2 and N2H4 molecules, this catalytic action of organometallic compounds leads to elevated rate of the O2–N2H4 fuel cell reaction.

Graphical abstract Ferrocene and its derivatives are vital class of organometallic compounds having extensive biological activities. Six novel ferrocene-based thiosemicarbazones have been synthesized through the condensation reaction of acetyl ferrocene with differently substituted thiosemicarbazide. Furthermore, we used state-of-the-art computational docking approach to explore the theoretical aspects for possible antiviral potential of our synthesized compounds. All the six compounds were docked with Mpro protein of SARS-CoV-2, which is very crucial protein for viral replication. Among the six derivatives, compounds 2 and 4 showed higher binding affinities with binding energy of − 6.7 and − 6.9 kcal/mol, respectively. The visualization of intermolecular interactions between synthesized derivatives and Mpro protein illustrated that each of compounds 2 and 4 forms two hydrogen bonds accompanied by important hydrophobic interactions. The comparison of binding affinities with some recently approved drugs like remdesivir, chloroquine and hydroxychloroquine molecules are also made. The calculated binding energies of remdesivir, chloroquine and hydroxychloroquine molecules with Mpro of COVID-19 was found to be − 7.00, − 5.20 and − 5.60 kcal/mol, respectively. The binding energy of compound 4 (− 6.9 kcal/mol) was almost equal to the remdesivir and greater than the binding energies of chloroquine and hydroxychloroquine. It is expected from the current investigation that our synthesized ferrocene-based thiosemicarbazones might have potential for drug against SARS-CoV-2. Supplementary Information The online version contains supplementary material available at 10.1007/s13738-021-02346-1.

Pt–CoTiO3 nanocatalysts were supported on RGO functionalized with the Cr(CO)6 and [(ƞ6-C6H6)Cr(CO)6] organometallic compounds and characterized for the oxygen reduction reaction (ORR). Different stoichiometric ratios of Cr(CO)6 gave mono- and bis-hexahapto complexes (RGO-Crtric and RGO2Cr) as a result of the displacement of the carbonyl groups, resulting in the Pt–CoTiO3/RGO-Crtric and Pt–CoTiO3/RGO2Cr nanocatalysts. In the reaction with (ƞ6-C6H6)Cr(CO)3, the arene ligand was retained and the three carbonyl groups disappeared, forming the RGO-Crbz complex (i.e., Pt–CoTiO3/RGO-Crbz). During the evaluation of catalytic activity for the ORR, Pt–CoTiO3/RGO-Crbz showed superior mass and specific activities for the ORR compared to the other nanocatalysts. Characterization of Pt–CoTiO3/RGO-Crbz showed that Cr4+, Cr3+, and Cr6+ are formed after functionalization. The results in this work demonstrated that functionalization of RGO with Cr organometallic compounds enhances the catalytic activity for the ORR of nanocatalysts with application in anion exchange membrane fuel cells (AEMFC).

The synthesis of nitrogen-containing heterocycles, including natural alkaloids and other compounds presenting different types of biological activities have proved to be successful employing chiral sulfinyl imines derived from tert-butanesulfinamide. These imines are versatile chiral auxiliaries and have been extensively used as eletrophiles in a wide range of reactions. The electron-withdrawing sulfinyl group facilitates the nucleophilic addition of organometallic compounds to the iminic carbon with high diastereoisomeric excess and the free amines obtained after an easy removal of the tert-butanesulfinyl group can be transformed into enantioenriched nitrogen-containing heterocycles. The goal of this review is to the highlight enantioselective syntheses of heterocycles involving the use of chiral N-tert-butanesulfinyl imines as reaction intermediates, including the synthesis of several natural products. The synthesis of nitrogen-containing heterocycles in which the nitrogen atom is not provided by the chiral imine will not be considered in this review. The sections are organized according to the size of the heterocycles. The present work will comprehensively cover the most pertinent contributions to this research area from 2012 to 2020. We regret in advance that some contributions are excluded in order to maintain a concise format. We thank the continuous financial support from the Spanish Ministerio de Economía y Competitividad (MINECO; project CTQ2014-53695-P, CTQ2014-51912-REDC, CTQ2016-81797-REDC, CTQ2017-85093-P), Ministerio de Ciencia, Innovación y Universidades (RED2018-102387-T, PID2019-107268GB-100), FEDER, the Generalitat Valenciana (PROMETEOII/2014/017), and the University of Alicante (VIGROB-068). We are also grateful for the financial support from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).

The binary hydride, diisobutylaluminum borohydride [(iBu)2AlBH4], synthesized from diisobutylaluminum hydride (DIBAL) and borane dimethyl sulfide (BMS) has shown great potential in reducing a variety of organic functional groups. This unique binary hydride, (iBu)2AlBH4, is readily synthesized, versatile, and simple to use. Aldehydes, ketones, esters, and epoxides are reduced very fast to the corresponding alcohols in essentially quantitative yields. This binary hydride can reduce tertiary amides rapidly to the corresponding amines at 25 °C in an efficient manner. Furthermore, nitriles are converted into the corresponding amines in essentially quantitative yields. These reactions occur under ambient conditions and are completed in an hour or less. The reduction products are isolated through a simple acid-base extraction and without the use of column chromatography. Further investigation showed that (iBu)2AlBH4 has the potential to be a selective hydride donor as shown through a series of competitive reactions. Similarities and differences between (iBu)2AlBH4, DIBAL, and BMS are discussed.

Fast addition of highly polar organometallic reagents (RMgX/RLi) to cyclic carbonates (derived from CO2 as a sustainable C1 synthon) has been studied in 2-methyltetrahydrofuran as a green reaction medium or in the absence of external volatile organic solvents, at room temperature, and in the presence of air/moisture. These reaction conditions are generally forbidden with these highly reactive main-group organometallic compounds. The correct stoichiometry and nature of the polar organometallic alkylating or arylating reagent allows straightforward synthesis of: highly substituted tertiary alcohols, β-hydroxy esters, or symmetric ketones, working always under air and at room temperature. Finally, an unprecedented one-pot/two-step hybrid protocol is developed through combination of an Al-catalyzed cycloaddition of CO2 and propylene oxide with the concomitant fast addition of RLi reagents to the in situ and transiently formed cyclic carbonate, thus allowing indirect conversion of CO2 into the desired highly substituted tertiary alcohols without need for isolation or purification of any reaction intermediates.

We present the η3‐coordination of the 2‐phosphaethynthiolate anion in the complex (PN)2La(SCP) (2) [PN=N‐(2‐(diisopropylphosphanyl)‐4‐methylphenyl)‐2,4,6‐trimethylanilide)]. Structural comparison with dinuclear thiocyanate‐bridged (PN)2La(μ‐1,3‐SCN)2La(PN)2 (3) and azide‐bridged (PN)2La(μ‐1,3‐N3)2La(PN)2 (4) complexes indicates that the [SCP]− coordination mode is mainly governed by electronic, rather than steric factors. Quantum mechanical investigations reveal large contributions of the antibonding π*‐orbital of the [SCP]− ligand to the LUMO of complex 2, rendering it the ideal precursor for the first functionalization of the [SCP]− anion. Complex 2 was therefore reacted with CAACs which induced a selective rearrangement of the [SCP]− ligand to form the first CAAC stabilized group 15–group 16 fulminate‐type complexes (PN)2La{SPC(RCAAC)} (5 a,b, R=Ad, Me). A detailed reaction mechanism for the SCP‐to‐SPC isomerization is proposed based on DFT calculations., The first stable coordination of the 2‐phosphaethynthiolate ([SCP]−) anion at a Lewis‐acidic lanthanum(III) ion and its subsequent rearrangement to form a substituted heavy “fulminate‐like” anion, induced by cyclic alkyl amino carbenes, are reported.

This Perspective focuses on the ability of chemical shift to identify and characterize the electronic structure and associated reactivity of molecules and materials. After a general introduction on NMR parameters, we will show selected examples where the chemical shift of various NMR active nuclei has been used to investigate and understand electronic properties, with a particular focus on organometallic compounds and inorganic materials with relevance to catalysis. We will demonstrate how the NMR parameter of probe molecules and ligands can be used to elucidate the nature of active sites and how they can help to understand and predict their reactivity. Lastly, we will give an overview over recent advances in deciphering metal NMR parameters. Overall, we show how chemical shift is a reactivity descriptor that can be analyzed and understood on a molecular level.

In this work, the efficiencies of three organometallic yttrium precursors used to produce YSZ coatings by plasma-enhanced chemical vapor deposition were studied. Yttrium (III) acetylacetonate, Y (acac)3, yttrium (III) hexafluoroacetylacetonate, Y (acacF6)3, and yttrium (III) tris(2,2,6,6-tetramethyl-3,5-heptanedionate), Y (tmhd)3, were used to stabilize the cubic phase in zirconia deposited at temperatures from 500 to 800 °C. Our results showed that at temperatures between 500 and 600 °C, Y (tmhd)3 appeared to be the most efficient dopant as it introduced the highest concentration of yttria (1–2.7 mol%) with only 6.4–5.6 at.% carbon. However, at 700 and 800 °C, Y (acac)3 introduced twice as much yttria (8–15 mol%) as Y (tmhd)3 with almost the same amount of carbon (5.4–3 at.%). Conversely, Y (acacF6)3 was the least efficient as it maintained a low concentration of yttria of around 0.7–1.8 mol% with 3.6–8.2 at.% carbon for all the deposition temperatures. Among these precursors, only Y (acac)3 surpassed 8 mol% yttria and achieved a fully stabilized cubic phase at 800 °C, with the remaining samples stabilizing only the tetragonal phase. The tetragonal phase was stabilized due to the formation of crystallites of around 10 nm. The observed difference in the efficiency of the three precursors was correlated to important differences in their decomposition behavior as observed by mass spectrometry and thermogravimetry/differential scanning calorimetry.

Introduction. Increased content of organic substances in natural waters, expanding the list of input substances to water bodies, owing to industrial and economic activities of a person, and climate changes is an urgent issue. Against this background, compounds with unknown chemical and toxic properties are likely to appear. The purpose of this study is to collect data concerning the ways for organic compounds entering water bodies and the human body, study data on interaction mechanisms of organic substances with metals, reveal the fate of known organic chelators, complexing agents as well as organometallic compound shaped by them inside the body. The literature search was carried out in Scopus, Web of Science, CyberLeninka databases. Sources of organic substances entering water bodies, properties of organic substances. There are three types of organic substances in water bodies, divided by the sources of their occurrence (inflow): terrigenous origin, shaped inside water bodies and coming from man-made sources. Organic compounds may produce soluble and insoluble compounds with metals and colloids. Mechanisms of interaction of organic substances with metals. Bonding of organic substances takes place by the type of chelation and complexation. There are factors for bonding: functional group content, the molecular mass of substances, ion radius, and competitive interaction with binding sites. Substances having binding properties include phenolic compounds, carboxylic acids, polysaccharides, and flavonoids. Considering that phenolic compounds are located in large quantities in plant and animal tissues, this group of compounds has been researched more thoroughly in terms of interactions with metals and toxicometry. Intake of organic and organometallic compounds into the body, their kinetics, metabolism and decay. Organic compounds, chelates, and complexes enter the body with drinking water, food, and drugs. They are also generated in the body, including by replacing ions. Data on biochemical and toxicological studies of currently known compounds is given

Gold is an inert coinage metal forming stable coordination compounds with various ligands specifically N-heterocyclic carbenes (NHCs). NHCs react with aurate salts as well as other inorganic salts ...

Catalysis is among the most promising and fascinating techniques used in various research fields and industries. Heterogeneous catalysts have received more attention than homogeneous catalysts owing to reusability and selectivity issues. Accordingly, metal–organic frameworks (MOFs) are excellent tools for converting homogeneous catalysts into heterogeneous catalysts. MOFs are organic–inorganic hybrid materials with a metal node and an organic linker connected with each other via a coordinate bond that have been developed as encouraging candidates for various applications. The heterogenization of a homogeneous catalyst by developing hybrid materials with MOFs is an attractive new field, combining the properties of both compounds to generate new hybrid heterogeneous catalysts. These new hybrid materials have the benefits of both the organometallic compound and the MOF constituents. As homogeneous catalyst recovery is difficult, this new approach allows the same catalyst to be used, but now exhibiting heterogeneous properties. This review summarizes versatile approaches to the encapsulation of a wide range of organometallic compounds (OMCs) in MOFs to generate OMC@MOFs for catalytic applications. After encapsulation, these OMCs have been used to form nanoparticles (MNP@MOFs) that have been applied to different organic transformations. Although other materials, including zeolites and silica, have also been used for heterogenization, the present review places emphasis on the use of MOFs in the process of heterogenization. The heterogenization of homogeneous organometallic catalysts by incorporation into MOFs using different strategies, MOF selection, OMC selection, and the use of hybrid heterogeneous catalysts in catalytic applications are discussed.

Four cobalt-containing organometallic compounds were synthesized for solid-state pyrolysis (SSP) to study the structure–property relationship between the precursors and the as-synthesized magnetic carbon nanocomposites (MCNs). In this research, the only saturated carbon atom in MC was replaced by a N, O or S atom, to produce precursors MN, MO and MS, respectively. It was found that the crystal phase of cobalt generated upon pyrolysis is dependent on the kind of heteroatom introduced into the precursor: fcc-Co for MC/MN, while the fcc/hcp-Co hybrid for MO/MS. Metal cobalt with different crystal phases has its special catalytic and magnetic properties. Thus, MCNs with very different morphologies, compositions and properties could be prepared by just altering one heteroatom in the precursors upon SSP. Uniform nanotubes were generated from pyrolysis of MC/MN, while nanospheres were generated from MO/MS. The obtained MCNs all show good magnetic properties with Ms ranging from 47.6 to 54.5 emu g−1. Due to the magnetic difference between fcc-Co and hcp-Co, the Ms values of MCNs obtained from MO/MS are slightly lower than those of MC/MN, but the Mr and Hc values of the former are 2 to 5 times higher than those of the latter.

In this review, we focus on metallocenes (e.g., ferrocene, ruthenocene, and cobaltocene/cobaltocenium), a class of prototypical organometallic compounds, as emerging stress-responsive building blocks for materials. In particular, they are used in the field of polymers as molecular ball-bearings, redox molecular motors, and mechanophores in response to varied force stimulus intensities. We present a workflow for a stress-responsive metallocene, the research techniques in various material phases, the factors impacting their mechanosensitivity, and the functional applications. Future prospects are briefly highlighted. This review provides fresh viewpoints and mechanistic insights to stimulate further studies in this field.

CO2 valorization into valuable chemicals has attracted much attention, among which carboxylative cyclization represents an appealing transformation strategy to synthesize heterocyclic compounds. Conventionally, the carboxylative cyclization comprises CO2 capture and subsequent nucleophilic attack of the resulting carboxylic anion to an unsaturated bond, by which the monofunctionalization of the unsaturated bond is realized and the heterocyclic compounds, such as 5-/6-membered cyclolactone, cyclocarbonate, and oxazolidinone, are accordingly generated. Nowadays, the CO2-participated multicomponent carboxylative cyclizations have evoked intense interest due to their ability to perform the bifunctionalization of the unsaturated bond in the ring-closing step, thus assembling complex molecules. Up to now, by activating the unsaturated bonds with functionalized reagents and designing cascade reactions of organometallic compounds, substituents including iodine, trifluoromethyl, perfluoroalkyl, alkyl, cyanoalkyl, allyl, aryl, phenoxy, allenyl, selenyl, amino, and phosphonyl groups have been incorporated into the cyclocarbonate or oxazolidinone compounds successfully through the multicomponent carboxylative cyclizations. Given the tremendous utility of this synthetic strategy in heterocyclic compound synthesis, this review summarizes the progress of multicomponent carboxylative cyclizations to spur the further development of this field.

An efficient approach to the synthesis of new types of Hoveyda–Grubbs catalysts containing an N→Ru bond in a six-membered chelate ring is proposed. The synthesis of the organometallic compounds is ...

Organometallic oligomeric compounds with dual-headed structure R’-(M-R-)nM-R’ were developed enabling the synthesis of triblock polyolefins. The compounds comprise divalent linkers (R) derived from...

Based on 2-(4-pyridyl)-terephthalate (H2pta) and oxalate ligands, two new lanthanide-containing coordination polymers (CPs), [Tb(pta)(C2O4)0.5(H2O)2)]·2H2O (1) and [Sm(pta)(C2O4)0.5(H2O)2)]·2H2O (2), have been synthesized under solvothermal conditions. The structures of both 1 and 2 have been determined by single-crystal X-ray diffraction. Infrared, elemental analysis, powder X-ray diffraction and thermogravimetric analysis data are also presented. The crystals of 1 and 2 exhibit isostructural layer-like networks, crystallizing in the triclinic space group P 1 ‾ $‾{1}$ . The layers are further stabilized and associated into 3D architectures through hydrogen bonding. Remarkably, the CPs 1 and 2 exhibit excellent water stability and remarkable thermostability with thermal decomposition temperatures of more than 420 °C.

Herein, we report a methodology that leads to the formation of Ru metallic sites, followed by the development and anchorage of Pt-Ru alloyed nanoparticles on the surface of Ordered Mesoporous Hollow Carbon Spheres (OMHCS). Along with the Ru sites, it is demonstrated that the functionalization promotes the formation of functional groups on the surface of the OMHCS. In a first stage, OMHCS are functionalized with the [(η6-C6H5OCH2CH2OH)RuCl2]2 (Ru-dim) and [(η6-C6H4CH(CH3)2CH3)RuCl2]2 (Ru-cym) organometallic compounds. Afterwards, Pt nanoparticles are dispersed by the microwave-assisted polyol method over the functionalized supports obtaining the low-metal content 5 wt. % Pt/OMHCSRu-dim and Pt/OMHCSRu-cym nanocatalysts. The degree of Ru alloyed is found to be around 35%. The low-Pt content Pt/OMHCSRu-cym and Pt/OMHCSRu-dim exhibit a higher catalytic activity for the Oxygen (OER) and the Hydrogen (HER) Evolution Reactions than the Pt/C benchmark and the Pt/OMHCS nanocatalysts. The overpotential for the OER at 10 mA cm-2 (ηOER) is 300 mV and 210 mV smaller at Pt/OMHCSRu-cym and Pt/OMHCSRu-dim compared to Pt/C, respectively. The corresponding values of the HER at -10 mA cm-2 (ηHER) are 14 and 18 mV smaller, respectively. The high catalytic activity of Pt/OMHCSRu-cym and Pt/OMHCSRu-dim has been attributed in part to the presence of Ru0 and RuO2 species from organometallic functionalization, and the modification of the d-valence band of Pt. Their high performance for the OER and the HER opens new lines of research for the design of nanocatalysts for alkaline electrochemical water splitting.

We report on the preparation of a series of phosphorus–nitrogen donor ligand complexes [M(CO)4(PN)], where M = Cr, Mo, W and PN is 2-(diphenylphosphino)ethylamine. The organometallic compounds were...

Organometallic compounds have become increasingly important in organic synthesis because of their high chemoselectivity and excellent reactivity. Recently, a variety of organometallic reagents were found to facilitate transition-metal-catalyzed cross-coupling reactions and nucleophilic addition reactions. Here, we have summarized the latest progress in cross-coupling reactions and in nucleophilic addition reactions with functionalized organometallic reagents present to illustrate their application value. Due to the tremendous contribution made by the Knochel group towards the development of novel organometallic reagents, this review draws extensively from their work in this area in recent years.Introduction1 Transition-Metal-Catalyzed Cross Couplings Involving Organo­zinc Reagents2 Transition-Metal-Catalyzed Cross Couplings Involving Organomagnesium Reagents3 Transition-Metal-Free Cross Couplings Involving Zn and Mg ­Organometallic Reagents4 Nucleophilic Additions Involving Zn and Mg Organometallic Reagents5 Cross-Coupling Reactions or Nucleophilic Additions Involving Mn, Al-, La-, Li-, Sm- and In-Organometallics6 Conclusion

The paper presents experimental data on convective heat and mass transfer during sublimation of a single spherical particle of a mixture of organometallic compounds Zr(dpm)4/Y(dpm)3 in a high-temperature flow of an inert gas (He, Ar). The influence of the carrier gas velocity and composition on the characteristics of the mass transfer processes is considered. Data on dynamics of changes in the size and temperature of a sample during sublimation are obtained.

Deltahedral nine-atom tetrel element Zintl clusters are promising building blocks for the straightforward solution-based synthesis of intermetalloid clusters through the reaction with organometallic compounds. Herein we report on novel coordination sites of metal-N-heterocyclic carbene (NHC) complexes to [Ge9] clusters and unexpected cluster isomerization. We present the synthesis of a series of coinage metal-NHC complexes of silylated [Ge9] clusters [NHCiPrCu(η4-Ge9{Si(TMS)3}3)] (1; TMS = trimethylsilyl) and [NHCRM(η4-Ge9{Si(TMS)3}2)]- (2a, M = Cu, R = iPr; 3a, M = Cu, R = Mes; 4a, M = Cu, R = Dipp; 5a, M = Ag, R = Dipp; 6a, M = Au, R = Dipp), in which the coinage metals coordinate to open rectangular cluster faces and act as additional cluster vertex atoms. Besides representing promising intermediates on the way to larger intermetalloid clusters, the formation of compound 1 shows that Cu-NHC fragments also coordinate to the open-square Ge faces of the tris-silylated [Ge9] clusters, contrasting the typical interactions with triangular faces of tris-silylated [Ge9] clusters. In compounds 3a and 4a bearing bulky NHC moieties, an unusual silyl group substitution pattern is observed in contrast to 2a, which corresponds to the silyl group arrangement of other metal complexes of bis-silylated [Ge9] clusters. In this context, potential silyl group migration mechanisms are discussed.

Mitigating ambient nitrogen dioxide (NO2 ) pollution via selective adsorption on porous materials is a promising approach to tackle such an increasingly pressing environmental health issue. However, very few porous adsorbents have sufficiently high NO2 adsorption capacity and good regenerability simultaneously. Here we attempt to address this challenge by developing π-backbonding adsorbents in the transition metal (TM) incorporated porphyrin metal-organic frameworks (PMOFs). Breakthrough experiments show that PMOFs with inserted TMs achieve appreciable NO2 capacity and good regenerability. Combined in situ DRIFTS, synchrotron powder XRD, and DFT calculations reveal the adsorption mechanism: NO2 partially transforms to N2 O4 and interacts with transition metal via π-backbonding and Al-node via hydrogen bonding. This work affords new insights for designing next-generation adsorbents for ambient NO2 removal and presents PMOFs as a platform to tailor π-backbonding adsorbents.

Intriguing properties and functions are expected to implant into metal-organic layers (MOLs) to achieve tailored pore environments and multiple functionalities owing to the synergies among multiple components. Herein, we demonstrate a facile one-pot synthetic strategy to incorporate multiple functionalities into stable zirconium MOLs via secondary ligand pillaring. Through the combination of Zr6 -BTB (BTB=benzene-1,3,5-tribenzoate) layers and diverse secondary ligands (including ditopic and tetratopic linkers), 31 MOFs with multi-functionalities were systematically prepared. Notably, a metal-phthalocyanine fragment was successfully incorporated into this Zr-MOL system, giving rise to an ideal platform for the selective oxidation of anthracene. The organic functionalization of two-dimensional MOLs can generate tunable porous structures and environments, which may facilitate the excellent catalytic performance of as-synthesized materials.

In wake of emerging applications of organotellurium compounds in biological and material science avenues, the current review describes their key synthetic methodologies while focusing the synthesis of organotellurium compounds through five ligand-to-metal linkages including carbon; carbon-oxygen; carbon-nitrogen; carbon-metal; carbon-sulfur to tellurium. In all of these linkages whether tellurium links with ligands through a complicated or simple pathways, it is often governed through electrophilic substitution reactions. The present study encompasses these major synthetic routes so as to acquire comprehensive understanding of synthetic organotellurium compounds.

The first palladium organometallic compounds bearing N-trifluoromethyl N-heterocyclic carbenes have been synthesized. These η3 -allyl complexes are potent antiproliferative agents against different cancer lines (for the most part, IC50 values fall in the range 0.02-0.5 μm). By choosing 1,3,5-triaza-7-phosphaadamantane (PTA) as co-ligand, we can improve the selectivity toward tumor cells, whereas the introduction of 2-methyl substituents generally reduces the antitumor activity slightly. A series of biochemical assays, aimed at defining the cellular targets of these palladium complexes, has shown that mitochondria are damaged before DNA, thus revealing a behavior substantially different from that of cisplatin and its derivatives. We assume that the specific mechanism of action of these organometallic compounds involves nucleophilic attack on the η3 -allyl fragment. The effectiveness of a representative complex, 4 c, was verified on ovarian cancer tumoroids derived from patients. The results are promising: unlike carboplatin, our compound turned out to be very active and showed a low toxicity toward normal liver organoids.

Modulating the size and dispersion of metal particles is highly desirable in nanocatalysis. Herein highly dispersed ruthenium clusters confined in nitrogen-doped carbon (RuNC) were synthesized by a one-pot pyrolysis of Ru(phen)3 organometallic compounds and glucose. The size of the Ru clusters was finely controlled at a cluster level (1.7 nm) to expose more catalytic active sites. The interaction between the Ru clusters and N species not only facilitated the uniform dispersion, but also prevented the aggregation of Ru clusters. This cluster-level RuNC manifested extraordinary catalytic performance towards the hydrogen evolution reaction (HER) and was comparable to or even better than a commercial Pt/C catalyst in basic and acidic media, respectively. Moreover, based on density functional theory (DFT) calculations, it was demonstrated that the N dopants in the carbon framework efficiently tailored the charge density distribution of the Ru centres and promoted the adsorption of H* on the catalyst, thus contributing to the high catalytic activity.

Highly polarized organometallic compounds of s-block elements are added smoothly to chiral N-tert-butanesulfinyl imines in the biodegradable d-sorbitol/choline chloride eutectic mixture, thereby granting access to enantioenriched primary amines after quantitatively removing the sulfinyl group. The practicality of the method is further highlighted by proceeding at ambient temperature and under air, with very short reaction times (2 min), enabling the preparation of diastereoisomeric sulfinamides in very good yields (74-98 %) and with a broad substrate scope, and the possibility of scaling up the process. The method is demonstrated in the asymmetric syntheses of both the chiral amine side-chain of (R,R)-Formoterol (96 % ee) and the pharmaceutically relevant (R)-Cinacalcet (98 % ee).

The iodine(III) reagents vinylbenziodoxolones (VBX) were employed to vinylate a series of aliphatic and aromatic thiols, providing E‐alkenyl sulfides with complete chemo‐ and regioselectivity, as well as excellent stereoselectivity. The methodology displays high functional group tolerance and proceeds under mild and transition metal‐free conditions without the need for excess substrate or reagents. Mercaptothiazoles could be vinylated under modified conditions, resulting in opposite stereoselectivity compared to previous reactions with vinyliodonium salts. Novel VBX reagents with substituted benziodoxolone cores were prepared, and improved reactivity was discovered with a dimethyl‐substituted core., Novel vinylation reagent: The iodine(III) reagents vinylbenziodoxolones (VBX) have been employed to vinylate aliphatic and aromatic thiols, as well as mercaptothiazoles. The methodology proceeds under mild and transition metal‐free conditions to provide alkenyl sulfides with excellent stereoselectivity. A novel VBX reagent with a substituted benziodoxolone core had superior efficiency.

Tungsten is an elegant substance, and its compounds have great significance because of their extensive range of applications in diverse fields such as in gas sensors, photocatalysis, lithium ion batteries, H2production, electrochromic devices, dyed sensitized solar cells, microchip technology, and liquid crystal displays. Tungsten compounds exhibit a more efficient catalytic behavior, and tungsten-dependent enzymes generally catalyze the transfer of an oxygen atom to or from a physiological donor/acceptor with the metal center. Furthermore, tungsten has an n-type semiconductor band gap. Tungsten forms complexes by reacting with several elements such as H, C, N, O, and P as well as other numerous inorganic elements. Interestingly, all tungsten reactions occur at ambient temperature, usually with tetrahydrofuran and dichloromethane under vacuum. Tungsten has extraordinarily high-temperature properties, making it very useful for X-ray production and heating elements in furnaces. Tungsten coordinates with diverse nonmetallic elements and ligands and produces interesting compounds. This article describes an overview of the synthesis of various organometallic compounds of tungsten.

The CVD-method of organometallic compounds is a universal method of obtaining functional metal coatings on substrates of various chemical composition and configuration. The essence of the method is the evaporation (sublimation) of the organometallic compound in the reactor of the metallization unit and the deposition of metal on the substrate heated to the decomposition temperature of the initial reagent. This article presents the results of research work group of authors to create the algorithm of development safe methods foe depositing metallic coatings by CVD-method. The increase of the industrial safety of metallization is achieved due to automation of the process, equipping the plant for the application of metal coatings with locking and alarm systems. The ecological nature of the CVD-method, in which extremely hazardous substances were used as initial reagents, was ensured by sealing equipment and conducting the process in a closed cycle with the possibility of re-use of the reagents. This eliminated the flow of pollutants into the environment and allowed the implementation of the principles of resource and energy conservation.

Studies on N2 activation and transformation by transition metal hydride complexes are of particular interest and importance. The synthesis and diverse transformations of a dinitrogen dititanium hydride complex bearing the rigid acridane-based acri PNP-pincer ligands {[(acri PNP)Ti]2 (μ2 -η1 :η2 -N2 )(μ2 -H)2 } are presented. This complex enabled N2 cleavage and hydrogenation even without additional H2 or other reducing agents. Furthermore, diverse transformations of the N2 unit with a variety of organometallic compounds such as ZnMe2 , MgMe2 , AlMe3 , B(C6 F5 )3 , PinBH, and PhSiH3 have been well established at the rigid acri PNP-ligated dititanium framework, such as reversible bonding-mode change between the end-on and side-on/end-on fashions, diborylative N=N bond cleavage, the formal insertion of two dimethylaluminum species into the N=N bond, and the formal insertion of two silylene units into the N=N bond. This work has revealed many unprecedented aspects of dinitrogen reaction chemistry.

Summary Transition-metal-catalyzed cross-coupling reactions between naturally abundant sp3-hybridized carbon centers facilitate access to diverse molecules with complex three-dimensional structures. Organometallic compounds are among one of the most powerful reagents that are broadly used in carbon–carbon bond formations. Although sp2-hybridized organometallic compounds are widely employed in cross-couplings, sp3-hybridized organometallic coupling partners are less developed. Herein, we report visible-light-induced single nickel-catalyzed C(sp3)–C(sp3), C(sp3)–C(sp2), and C(sp3)–C(sp) cross-coupling reactions using alkylzirconocenes, which are easily generated in situ from terminal or internal unactivated alkenes through hydrozirconation and chain walking. This method is mild and applicable for a large range of substrates including primary, secondary, tertiary alkyl, aryl, alkenyl, alkynyl halides, and a variety of alkenes. Mechanistic studies suggest a novel nickel-catalyzed radical cross-coupling pathway, which represents the first visible-light-induced transformation of alkylzirconocenes.

Gallium nitride heterostructures on silicon substrates were grown by the method of gas-phase epitaxy from organometallic compounds. Based on them, transistors with a total gate width of 7.92 mm were created. The influence of the architecture of buffer layers on the characteristics of heterostructures and test transistors based on them is studied. Powerful transistors were obtained with an output pulse power of 45 W at a frequency of 1 GHz with a supply voltage of 28 V. The maximum efficiency of the transistor was 55%.

Different binary PtxPd1-x alloys supported on Vulcan carbon XC-72R were synthesized by the displacement of ligands from organometallic compounds to be used as anodic electrode for methanol electro-oxidation in alkaline medium. The influence of the Pd addition during the synthesis of PtxPd1-x alloys in presence of octylamine as stabilizer was analyzed in terms of structure, chemical composition and electroactivity in the methanol oxidation reaction. The X-ray photoelectron spectroscopy analysis showed that the surface of the electrodes consisted of a metallic mixture and oxide states, which confirmed the change in the electronic properties during the alloy formation. The current density of Pt30Pd70/C during CV measurements was about 2.1 times higher than the one observed with Pt/C electrodes. The CO tolerance was also slightly improved under similar conditions. The work findings indicate that stabilized Pt30Pd70/C binary alloys can be used to design highly active anodic catalysts with potential applications in direct methanol fuel cells (DMFCs).

Magnetic nanoparticles (MNPs) are important functional materials for applications ranging from information storage to biomedicine. In comparison with the traditional synthetic approaches, the preparation of MNPs from the pyrolysis of organometallic polymers has attracted increasing attention, due to their rich species, excellent solution processability, and relatively good control of the properties of the yielded MNPs. This review summarizes the recent progress of cobalt-containing organometallic polymers and their utilization as precursors for the preparation of functional magnetic nanostructures through controllable pyrolysis. For comparison, the pyrolysis of Co-containing organometallic compounds with a precise molecular structure was also involved to underline the structure–property relationship between the organometallic precursors and the as-generated products. Furthermore, novel approaches are introduced for the in situ generation of magnetic nanoarrays with adjustable magnetic properties through the self-assembly and subsequent low temperature thermolysis of Co-containing block metallopolymers. Moreover, the preparation of elastic magnetic hydrogels is also presented through the low temperature thermolysis (120 °C) and subsequent wetting of Co-containing triblock organometallic copolymers. Future perspectives and challenges in the field are discussed towards the controlled fabrication of MNPs with desired morphology, size and properties.

Macrocyclic oligoesters (MCOs) derived from biomass such as those prepared from alkylene alkanedioates and 2,5-furandicarboxylates are suitable compounds for ring opening polymerization (ROP) to produce high molecular weight bio-based polyesters. The synthetic procedures that have been recently developed to obtain these MCOs in good yields, their ROP either alone or together with other cyclic compounds, and their recovery by cyclodepolymerization of the final polyesters are the main topics covered in this review. Both organometallic compounds and enzymes such as Candida antarctica lipase B are the catalytic systems used for all reactions. This synthetic approach based on ROP of MCOs derived from renewable sources opens a green pathway for a circular economy in plastics.

The addition of organometallic compounds to imines is a direct way for accessing α-branched secondary amines which are found in numerous bioactive molecules. Although convenient, such reactions typically involve the formation and isolation of the nucleophile in the case of Grignard reactions, or the in situ formation of the nucleophile for Barbier reactions, leading to stoichiometric amounts of metallic wastes. Herein, we report the direct alkylation of imines with redox-active esters by visible light photoorganocatalysis. With Rose bengal as inexpensive photocatalyst, and green light as sustainable energy source, the synthesis of a wide range of amines and θ-amino esters was achieved from inexpensive feedstock chemicals, in a highly modular fashion.

The prevalent synthesis of colloidal metal oxide nanocrystals relies on the synthesis of various precursors, such as organometallic compounds, which are usually sensitive to moisture or oxygen and generally expensive. Based on the economic efficiency, the costs of the starting materials and synthetic process should be addressed. Herein, a general simple synthetic procedure from inexpensive and nontoxic precursors is developed. Under optimized reaction conditions, MnO nanocrystals are synthesized with commercially purchased bulk manganese oxides as starting materials, such as MnO, MnO2, and Mn3O4. The size and morphologies of nanoparticles are modulated by tuning the types and dosage of coating agents. Moreover, this synthetic strategy is further extended to other nanoparticles including Fe3O4 nanocrystals and FeMnOx nanocrystals. Furthermore, Re doped MnO nanocrystals exhibiting fluorescence properties have been synthesized with this method, which endows the fluorescence properties to these oxide nanocrystals.

International audience; Rational characterization of most organometallic compounds is hampered by their high reactivity, in particular, toward oxygen and water. Mass spectrometry experiments require physical introduction of the sample in the ionization source. So, the main challenge is to transfer air-sensitive organometallic compounds from inert atmosphere to the ionization source. In this aim, we have developed an easy technique that allows the analysis of air-sensitive compounds using the atmospheric solid analysis probe (ASAP). This method consists of a glass capillary filled with the sample (solid or liquid) and sealed by a paraffin plug to maintain the inert sample until the ionization process. It is illustrated through the structural characterization of a new highly air-sensitive dinuclear zirconium complex supported by an original switchable stilbene platform.