Reaction Of Styrene Oxide Research Articles

Copper-Catalyzed Three-Component Synthesis of β-Hydroxysulfides from Styrene Oxide, Aryl Iodide, and Carbon Disulfide.

A copper-catalyzed three-component coupling reaction of styrene oxide, aryl iodide, and carbon disulfide for the construction of β-hydroxysulfides has been developed. In this process, readily available CS2 was used as the sulfur source to construct C-S bonds for the synthesis of phenyl-β-hydroxysulfides and (benzo[d]thiazol)-β-hydroxysulfides. This process features mild reaction conditions, simple operation, and wide substrate scope (>50 examples).

Investigation and Comparison of Catalytic Methods to Produce Green CO2-Containing Monomers for Polycarbonates

The preparation of CO2-containing polymers with improved degradation properties is still very challenging. An elegant method for preparing these polymers is to use CO2-containing monomers in ring-opening polymerizations (ROP) which are particularly gentle and energy-saving methods. However, cyclic carbonates are required for this which are not readily available. This paper therefore aims to present the optimization and comparison of two synthesis methods to obtain cyclic carbonates for ROP. Within this work, cyclic styrene carbonate was synthesized from readily available raw materials by using a Jacobsen catalyst for the reaction of styrene oxide and carbon dioxide or an organocatalyst for the transesterification of methyl carbonate with 1-phenyl-1,2-ethanediol. The latter performed with 100% selectivity to the desired styrene carbonate, which was succesfully tested in ROP, producing an amorphous thermoplastic polymer with a TG of 185 °C.

Porous Coordination Polymer MOF-808 as an Effective Catalyst to Enhance Sustainable Chemical Processes.

The improvement of sustainable chemical processes plays a pivotal role in safe environmental and societal development, for example, by reducing the use of hazardous substances, preventing chemical waste, and improving the efficiency of chemical reactions to obtain added-value compounds. In this context, the porous coordination polymer MOF-808 (MOF, metal-organic framework) was prepared by a straightforward method in water, at room temperature, and was unequivocally characterized by powder X-ray diffraction, vibrational spectroscopy, thermogravimetric analysis, and scanning electron microscopy. MOF-808 material was applied for the first time as catalysts in ring-opening aminolysis reactions of epoxides. It demonstrated high activity and selectivity for reactions of styrene oxide and cyclohexene oxide with aniline, using a very low amount of an eco-sustainable solvent (0.5 mL of EtOH), at 70 °C. Moreover, MOF-808 demonstrated high stability in the catalytic reaction conditions applied, and a notable reuse capacity of up to 20 consecutive reaction cycles, without significant variation in its catalytic performance. In fact, this Zr-based porous coordination polymer prepared by environment-friendly conditions proved to be a novel efficient heterogeneous catalyst, promoting the ring-opening reaction of epoxides under more sustainable conditions, and using a very low amount of catalyst.

2D Graphene Oxide Membrane Nanoreactors for Rapid Directional Flow Ring-Opening Reactions with Dominant Same-Configuration Products.

Nanoconfinement within enzymes can increase reaction rate and improve selectivity under mild conditions. However, it remains a great challenge to achieve chemical reactions imitating enzymes with directional molecular motion, short reaction time, ≈100% conversion, and chiral conversion in artificial nanoconfined systems. Here, directional flow ring-opening reactions of styrene oxide and alcohols are demonstrated with ≈100% conversion in <120 s at 22 °C using graphene oxide membrane nanoreactors. Dominant products have the same configuration as chiral styrene oxide in confined reactions, which is dramatically opposed to bulk reactions. The unique chiral conversion mechanism is caused by spatial confinement, limiting the inversion of benzylic chiral carbon. Moreover, the enantiomeric excess of same-configuration products increased with higher alkyl charge in confined reactions. This work provides a new route to achieve rapid flow ring-opening reactionswith specific chiral conversion within 2D nanoconfined channels, and insights into the impact of nanoconfinement on ring-opening reaction mechanisms.

Molybdenum-maltolate as a molybdopterin mimic for bioinspired oxidation reaction.

A novel cis-dioxomolybdenum(VI)-maltolate [MoO2(Mal)2] (1) is prepared as a stable molybdopterin model for the biomimetic catalysis of the oxidation of hypoxanthine in acetonitrile-water at room temperature. Compound 1 efficiently catalyzes the oxidation reaction of toluene, diphenylmethane, and styrene. Cyto- and oral-toxicity studies suggest its tremendous potential for application as a molybdenum supplement.

Tartaric acid-derived chiral carbon nanodots for catalytic enantioselective ring-opening reactions of styrene oxide.

Chiral carbon nanodots (CNDs) were fabricated through the hydrothermal processing of sulfanilic acid and chiral tartaric acid, exhibiting outstanding catalytic performance for the chiral catalysis of the ring-opening reaction. Furthermore, the catalytic mechanism was proposed to understand the link between the chiral structure and the performance of the catalyst.

Cu(II) and Mo(VI) Schiff base complexes immobilized on magnetic multiwalled carbon nanotubes: Oxidation of olefins and theoretical study

In this study, magnetic multiwalled carbon nanotubes (MMWCNT@SiO2) were anchored with phenylene diamine and subsequently prepared as Schiff base through mono condensation with salicylaldehyde, resulting in MMWCNT@SiO2/Schiff base. This was then complexed with either copper acetate monohydrate or molybdenum oxide to form MMWCNT@SiO2/Schiff base/M (M=Cu, MoO2). The prepared samples were characterized with FTIR, EDS, SEM and XRD. The catalytic behavior of the prepared samples was studied in the oxidation reaction. The results revealed that MMWCNT@SiO2/Schiff base/M (M=Cu, MoO2) effectively catalyzed the oxidation reaction of α-methyl styrene leading to more than 99% conversion and selectivity of acetophenone. In addition to the experimental investigations, theoretical calculations were conducted using DFT calculations to provide further insights into the results.

Significantly boosted activity for styrene oxidation through simultaneous regulation of porosity and copper sites in microporous metal–organic framework Cu-BTC

Herein, a series of novel HP-DEMOFs were prepared and employed as catalysts for the heterogeneous styrene oxidation reaction. They exhibited much higher conversion than that of the microporous Cu-BTC structure under the same reaction conditions.

Stimuli-Responsive Polymer Stabilized Iron Oxide Nanoparticle as Green Catalyst for Styrene Oxidation Reaction

Stimuli-Responsive Polymer Stabilized Iron Oxide Nanoparticle as Green Catalyst for Styrene Oxidation Reaction

Defective Metal‐Organic Frameworks with Tunable Porosity and Metal Active Sites for Significantly Improved Performance in Styrene Oxidation

Metal active sites and sufficient porosity in metal-organic frameworks (MOFs) are crucial parameters determining the performances of catalysis, guest molecule adsorption, etc. Herein, through in situ introduction of Ru sites with different levels to Cu-BTC structure together with post-synthetic activation at 180 °C, a series of hierarchically porous CuRu-BTC (HP-CuRu-BTC) MOFs were obtained. Besides, selective thermal decomposition (STD) treatment was carried out at 240 °C to further tune the hierarchical pores and metal sites, yielding rare case of metal nanoparticles (NPs)@HP-CuRu-BTC composites. After full characterization by XRD, N2 physisorption, SEM, ICP and XPS, these HP-CuRu-BTC and NPs@HP-CuRu-BTC samples possess high surface area (682-1199 m2 g-1 ), hierarchical pores and highly distributed metal sites with reduced oxidation states (Cu+ and Ru2+ ), indicating regulation of both metal sites and hierarchical pores. The HP-CuRu-BTC and NPs@HP-CuRu-BTC were further employed as catalysts for the heterogeneous styrene oxidation reaction under mild condition. Compared to microporous Cu-BTC with unary metal component, HP-CuRu-BTC-3 and NPs@HP-CuRu-BTC-3 exhibited more than 2 times higher styrene conversion after 7 hours reaction under same condition.

Chemorobust 4p-5p {InPb}-organic framework for efficiently catalyzing cycloaddition of CO2 with epoxides and deacetalization-Knoevenagel condensation

Due to that the high charge density and small radius render In3+ cation a stronger Lewis acidity, multifunctional nanoporous In-MOFs have become one of the most promising catalysts for their high activity. Herein, the solvothermal self-assembly by employing 2,4,6-tri (2,4-dicarboxyphenyl)pyridine (H6TDP) as organic linker leads to a robust honeycomb skeleton of {[(CH3)2NH2][InIIIPbII(TDP) (H2O)]⋅3DMF⋅3H2O}n (NUC-52) with the merits of nanoscopic channels, high porosity (61.3%), large specific surface area, and thermal stability. To the best of our knowledge, this is the first 4p-5p heterometallic {InIIIPbII} cluster-based nano-porous host framework, whose activated state possesses the coexistence of Lewis acid-base sites including 7-coordinated Pb2+ ions, 4-coordinated In3+ ions, uncoordinated carboxyl oxygen atoms, and Npyridine atoms. Performed catalytic experiments exhibited that activated NUC-52 owned the high catalytic activity on the cycloaddition reactions of styrene oxide with CO2 under mild conditions with excellent turnover number (2475) and turnover frequency (619 h−1). Moreover, activated NUC-52 could greatly accelerate the deacetalization-Knoevenagel condensation reactions of benzaldehyde dimethyl acetal and malononitrile. Hence, this work lays down the groundwork for constructing heterometallic cluster-based nanoporous MOFs with excellent Lewis acidic catalysis and chemical stability, which should be ascribed to the reasonable coordination arrangement between organic ligands and distinct metal ions according to the hard–soft acid–base (HSAB) theory.

Photo-induced photo-thermal synergy effect leading to efficient CO2 cycloaddition with epoxide over a Fe-based metal organic framework

It is crucial to design and synthesize a catalyst that can catalyze the production of cyclic carbonates from CO2 and epoxide under mild conditions. Herein, we successfully synthesized a two-dimensional metal organic framework FeTPyP, which displays an outstanding capability to catalyze the CO2 cycloaddition reaction under light irradiation with a yield of styrene carbonate as high as 106.13 mmol/(g h). Characterizations suggests that the major reason is due to (1) the synergistic effect between photocatalysis and thermocatalysis and (2) ultraviolet light can promote the ring-opening reaction of styrene oxide. This work provides an alternative approach to further design efficient heterogeneous catalysts for photo-induced CO2 cycloaddition reaction via coupling thermocatalysis and photocatalysis.

Insight of solvent effect on CeO2 catalyzed oxidation of styrene with tert-butyl hydroperoxide: A combined experimental and theoretical approach

Solvents influence the energetics of adsorbates on the solvent/ catalyst interface and thus control the catalytic activity and product distribution in heterogeneous catalysis. In the present work, influence of different polar organic solvents was studied on the styrene oxidation reaction using TBHP oxidant and CeO2 catalyst. The styrene conversion percentage and selectivity to styrene oxide increased with solvent polarity, while the opposite trend was observed for the other major product, benzaldehyde. Molecular Dynamic (MD) simulation studies were performed to calculate the adsorption energies of the reactant and products on the solvent/ CeO2 interface, together with Density Functional Theoretical (DFT) studies to understand the mechanistic pathway.

Fe-Mn-Si-O and Fe-Mn-Si-O/multi walled carbon nanotubes: synthesis, characteristics, adsorption and catalytic behavior

The mixed metal oxide nanostructures (Fe-Mn-Si-O) and Fe-Mn-Si-O/Multi walled carbon nanotubes (Fe-Mn-Si-O/MWCNT) were synthesized by a hydrothermal approach. The prepared samples were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Fe-Mn-Si-O has efficient removal of methylene blue (MB) and rhodamine b (RhB) from aqueous solution and both prepared compounds have an effective catalytic property in styrene oxidation reaction. In the process of exploring the adsorption conditions, the isotherms were found to be well fitted by Langmuir and Freundlich models. Moreover, the thermodynamic of RhB and MB adsorption was also studied. To investigate the adsorption mechanism, it was found that the adsorption kinetics of MB and RhB onto the Fe-Mn-Si-O surface was best described by the pseudo second-order model. In the next step, the catalytic behavior of Fe-Mn-Si-O and Fe-Mn-Si-O/MWCNT were studied in the styrene oxidation reaction, which yielded only benzaldehyde. Highlights Novel Fe-Mn-Si-O and Fe-Mn-Si-O/MWCNT were prepared by hydrothermal method. Fe-Mn-Si-O and Fe-Mn-Si-O/MWCNT were applied as catalyst in the styrene oxidation reaction The adsorption of MB and RhB was studied on the Fe-Mn-Si-O. Fe-Mn-Si-O and Fe-Mn-Si-O/MWCNT showed excellent behavior in catalytic reactions.

Atmospheric-pressure synthesis of glycerol carbonate from CO2 and glycerol catalyzed by protic ionic liquids

Under atmospheric pressure, a synthesis of glycerol carbonate was achieved in the one-pot reaction of CO2, glycerol, and styrene oxide with a 94% yield.

Ring-Opening Polymerization of ε-Caprolactone and Styrene Oxide-CO2 Coupling Reactions Catalyzed by Chelated Dehydroacetic Acid-Imine Aluminum Complexes.

A series of chelated dehydroacetic acid–imine-based ligands L1H~L4H was synthesized by reacting dehydroacetic acid with 2-t-butylaniline, (S)-1-phenyl-ethylamine, 4-methoxylbenzylamine, and 2-(aminoethyl)pyridine, respectively, in moderate yields. Ligands L1H~L4H reacted with AlMe3 in toluene to afford corresponding compounds AlMe2L1 (1), AlMe2L2 (2), AlMe2L3 (3), and AlMe2L4 (4). All the ligands and aluminum compounds were characterized by IR spectra, 1H and 13C NMR spectroscopy. Additionally, the ligands L1H~L4H and corresponding aluminum derivatives 1, 3, and 4 were characterized by single-crystal X-ray diffractometry. The catalytic activities using these aluminum compounds as catalysts for the ε-caprolactone ring-opening polymerization (ROP) and styrene oxide-CO2 coupling reactions were studied. The results show that increases in the reaction temperature and selective solvent intensify the conversions of ε-caprolactone to polycaprolactone. Regarding the coupling reactions of styrene oxide and CO2, the conversion rate is over 90% for a period of 12 h at 90 °C. This strategy dispenses the origination of cyclic styrene carbonates, which is an appealing concern because of the transformation of CO2 into an inexpensive, renewable and easy excess carbon feedstock.

Study of the Cycloaddition of CO2 with Styrene Oxide Over Six-Connected spn Topology MOFs (Zr, Hf) at Room Temperature.

A series of MOFs with a 6-connected spn topology were synthesized (MOF-808-(Zr, Hf), PCN-777-(Zr, Hf), MOF-818-(Zr, Hf)). Through the in situ DRIFTS of NH3 adsorption-desorption, we found that the activated catalyst mainly contains Lewis acid sites. The effects of different organic ligands on the Lewis acid of the Zr6 cluster were analyzed by XPS and NH3 -TPD, and the relative Lewis acidity of the same metal was obtained: PCN-777>MOF-808>MOF-818. In the Py-FTIR results, we confirmed that MOF-818 has a higher acid site density. In the activity test, MOFs with mesoporous structure showed better catalytic activity under normal temperature and pressure. Among them, MOF-818 can still maintain a high degree of crystallinity after catalysis. Finally, we use density functional theory to propose the mechanism of the cycloaddition reaction of carbon dioxide and styrene oxide. The results show that the metal is coordinated with styrene oxide and halogens attack the β carbon of the epoxide.

Water Chestnut Peel Facilitated Biogenic Synthesis of Zinc Oxide Nanoparticles and their Catalytic Efficacy in the Ring Opening Reaction of Styrene Oxide

AbstractSustainable initiatives using various biologically active plant materials have been receiving huge amount of attention in the immediate past. Herein, we present the plant mediated synthetic methodology for preparing zinc oxide (ZnO) nanoparticles (NPs) via a greener protocol using water chestnut peel (WCP), an agricultural bio‐waste whose versatility is well known both behaving as a stabilizing and reducing agent. This method of synthesis of ZnO NPs ensures a cost competitive, non‐toxic, economically viable and environmentally benign pathway while using WCP as efficient scaffolds. The crystalline nature and morphology of as synthesized NPs were confirmed using Powder X‐ray Diffraction (PXRD) and Scanning Electron Microscopy (SEM). Biogenically synthesized NPs have average crystalline size 20.49 nm and irregular spikes morphology. Furthermore, the biogenically synthesized ZnO NPs were utilized for catalysing the ring opening reaction of styrene oxide from aniline and aniline derivatives enabling the reaction reach up to 99 % yields. Motivated by the excellent conversion of ring opening reaction the biogenically synthesized catalyst has also been explored to earmark their versatility and efficiency for facilitating numerous organic transformations which simultaneously emphasise their role in safeguarding the environment.

Substrate–Solvent Crosstalk—Effects on Reaction Kinetics and Product Selectivity in Olefin Oxidation Catalysis

In this work, we explored how solvents can affect olefin oxidation reactions catalyzed by MCM-bpy-Mo catalysts and whether their control can be made with those players. The results of this study demonstrated that polar and apolar aprotic solvents modulated the reactions in different ways. Experimental data showed that acetonitrile (aprotic polar) could largely hinder the reaction rate, whereas toluene (aprotic apolar) did not. In both cases, product selectivity at isoconversion was not affected. Further insights were obtained by means of neutron diffraction experiments, which confirmed the kinetic data and allowed for the proposal of a model based on substrate–solvent crosstalk by means of hydrogen bonding. In addition, the model was also validated in the ring-opening reaction (overoxidation) of styrene oxide to benzaldehyde, which progressed when toluene was the solvent (reaching 31% styrene oxide conversion) but was strongly hindered when acetonitrile was used instead (reaching only 7% conversion) due to the establishment of H-bonds in the latter. Although this model was confirmed and validated for olefin oxidation reactions, it can be envisaged that it may also be applied to other catalytic reaction systems where reaction control is critical, thereby widening its use.

Enhancing catalytic epoxide ring-opening selectivity using surface-modified Ti3C2T x MXenes

MXenes are a new family of two-dimensional carbides and/or nitrides. Their 2D surfaces are typically terminated by O, OH and/or F atoms. Here we show that Ti3C2T x —the most studied compound of the MXene family—is a good acid catalyst, thanks to the surface acid functionalities. We demonstrate this by applying Ti3C2T x in the epoxide ring-opening reaction of styrene oxide (SO) and its isomerization in the liquid phase. Modifying the MXene surface changes the catalytic activity and selectivity. By oxidizing the surface, we succeeded in controlling the type and number of acid sites and thereby improving the yield of the mono-alkylated product to >80%. Characterisation studies show that a thin oxide layer, which forms directly on the Ti3C2T x surface, is essential for catalysing the SO ring-opening. We hypothesize that two kinds of acid sites are responsible for this catalysis: In the MXene, strong acid sites (both Lewis and Brønsted) catalyse both the ring-opening and the isomerization reactions, while in the Mxene–TiO2 composite weaker acid sites catalyse only the ring-opening reaction, increasing the selectivity to the mono-alkylated product.