Benzyl Alcohol Research Articles

Ortho-Alkynyl Benzyl Alcohols as C6 Synthons in Regioselective Construction of Polysubstituted Naphthalenes.

A straightforward methodology for the assembly of polysubstituted naphthalenes from ortho-alkynyl benzyl alcohols, enabled by using catalytic amounts of Tf2O, has been developed. This transformation not only features transition-metal free and without using other bases and additives but also provides a new synthetic application for ortho-alkynyl benzyl alcohols, i.e., as C6 synthons for the construction of PAHs.

Methyl salicylate affects fruit quality and aroma compounds of cherry during cold storage

Cherries are easy to soften and rot during the period of storage. This work was performed to assess the impact of different concentrations of methyl salicylate (MeSA, 0.1 mmol·L−1, 1.0 mmol·L−1, 2.0 mmol·L−1) on fruit quality and aroma compounds of cherries (‘Meizao’ and ‘Labins’) during cold storage (0 °C). Results showed that 1.0 mmol·L−1 of MeSA had the greatest effect on decreasing the respiration rate, improving the firmness and maintaining the soluble solids content (SSC) of cherry fruits. The main volatile aroma compounds in ‘Meizao’ and ‘Labins’ cherries were benzyl alcohol, hexanal, trans-2-hexenal, benzaldehyde and 2-hexenal. Additional observations revealed that MeSA could increase the ester aroma compounds and delay the loss of alcohol, aldehyde, ketone and terpenoid aroma compounds in postharvest cherries. Therefore, MeSA could effectively improve the quality and inhibit aroma loss of cherry fruits during cold storage.

Photothermal Methanation of CO with Benzyl Alcohol as a Hydrogen Source Using Au–Ni Alloy Catalyst

Photothermal Methanation of CO with Benzyl Alcohol as a Hydrogen Source Using Au–Ni Alloy Catalyst

Biodegradation of DEP, DIBP, and BBP by a psychrotolerant Sphingobium yanoikuyae strain P4: Degradation potentiality and mechanism study.

Phthalic acid esters (PAEs) are human made chemicals widely used as plasticizers to enhance the flexibility of plastic products. Due to the lack of chemical bonding between phthalates and plastics, these materials can easily enter the environment. Deleterious effects caused by this chemo-pollutant have drawn the attention of the scientific community to remediate them from different ecosystem. In this context, many bacterial strains have been reported across different habitats and Sphingobium yanoikuyae strain P4 is among the few psychrotolerant bacterial species reported to biodegrade simple and complex phthalates. In the present study, biodegradation of three structurally different PAEs viz., diethyl phthalate (DEP), di-isobutyl phthalate (DIBP), and butyl benzyl phthalate (BBP) have been investigated by the strain P4. Quantitative analyses through High-performance liquid chromatography (HPLC) revealed that the bacterium completely degraded 1g/L of DEP, DIBP, and BBP supplemented individually in minimal media pH 7.0 within 72, 54, and 120h of incubation, respectively, at 28°C and under shake culture condition (180rpm). In addition, the strain could grow in minimal media supplemented individually with up to 3g/L of DEP and 10.0g/L of DIBP and BBP at 28°C and pH 7.0. The strain also could grow in metabolites resulting from biodegradation of DEP, DIBP, and BBP, viz. n-butanol, isobutanol, butyric acid, ethanol, benzyl alcohol, benzoic acid, phthalic acid, and protocatechuic acid. Furthermore, phthalic acid and protocatechuic acid were also detected as degradation pathway metabolites of DEP and DIBP by HPLC, which gave an initial idea about the biodegradation pathway(s) of these phthalates.

Manganese‐catalyzed α‐alkylation of sulfones using alcohols via a hydrogen‐borrowing strategy: Synthesis of branched sulfones

Herein, we report an efficient and sustainable manganese‐catalyzed α‐C‐H bond alkylation methodology to synthesize branched sulfones via a hydrogen borrowing pathway. The air‐stable and phosphine‐free Mn‐catalyst, (NNN)Mn(II)Cl2 was synthesized by using an earth‐abundant, commercially available, and inexpensive precursor MnCl2.4H2O, and a stable NNN pincer i.e. [N‐((benzimidazole‐2‐yl)methyl)quinoline‐8‐amine] ligand system. Taking benzyl phenyl sulfones as substrates, and benzyl alcohol derivatives as alkylating agents, a range of branched sulfones were synthesized in 40‐82% isolated yields using (NNN)Mn(II)Cl2 complex as the catalyst under open‐air conditions. Control experiments and deuterium incorporation studies have also been conducted to investigate the possible reaction mechanism and to provide evidence for the hydrogen borrowing pathway.

Evaluation of Transiently O-6 Protected Guanosine Morpholino Nucleosides in PMO Synthesis

Here we present a novel strategy to synthesize O-6 protected morpholino guanosine monomers by trimethylsilylethyl group, 1-(4-azido-phenyl) ethan-1-ol and para methoxy benzyl alcohol, respectively. The introduction of this protecting group increases the solubility of the morpholino nucleoside which is crucial during PMO synthesis. HPLC analysis shows trimethylsilylethyl protected monomer gives better coupling efficiency in PMO synthesis compared to regular one. Moreover the nonpolar nature of the O-6 protected monomer facilitated the guanosine rich PMO block in solution.

Construction of a Dual-Function Mo-ZIS@Ti for Photocatalytic Benzyl Alcohol Oxidation and Hydrogen Evolution Performance.

The photocatalytic oxidation of benzyl alcohol and the simultaneous evolution of hydrogen from water are efficient dual-optimal routes. It is important to develop composite catalysts that combine redox properties and facilitate electron-hole separation and transport. Herein, the bimetallic-doped Mo-ZIS@Ti photocatalyst was designed and synthesized, and the selective oxidation of benzyl alcohol and hydrogen evolution by water splitting was realized at the same time. Under visible light irradiation, benzyl alcohol was completely converted with more than 99% selectivity for benzaldehyde, and the H2 production rate was 5.6 times higher than the initial ZIS. The exceptional catalytic performance was ascribed to utilizing Ti-MIL-125 as a precursor, wherein slowly releasing-doped Ti formed robust Ti-S bonds that quickly transfer electrons and reduce sites. Meanwhile, doping Mo effectively captures photogenerated holes and acts as active sites for oxidation reactions. Both experimental characterization and work function calculations demonstrate that the bimetallic synergism effectively modulates the electronic structure of ZIS, promotes the directional separation of electrons and holes, and significantly improves the photoactivity and stability of ZIS. This work contributes a route to obtain benzaldehyde and green hydrogen at the same time and also gives new insights for the construction and mechanism study of bimetallic-doping catalysts.

Brønsted Acid Catalyzed Dehydroxylative Cyanation of Benzylic Alcohols with Trimethylsilyl Cyanide Using 1,1,1,3,3,3‐Hexafluoro‐2‐propanol as a Solvent

A concise and direct cyanation of secondary and tertiary benzylic and allylic alcohols catalyzed by Brønsted acid has been developed using trimethylsilyl cyanide (TMSCN) as a cyanide source and 1,1,1,3,3,3‐hexafluoro‐2‐propanol (HFIP) as a solvent. The present transition metal‐free catalytic process is operationally simple to perform under “open‐flask” conditions and it is applicable to the preparation of a number of α‐arylacetonitriles as well as late‐stage material transformations. The effectiveness of the present protocol was further demonstrated by the first enantioselective synthesis and determination of the absolute configuration of verimol F.

Unraveling defect chemistry in doped-ceria catalyst for oxidative coupling of lignin-based aniline and benzyl alcohol

The defect chemistry of doped-ceria is vital but tangled for sustainable conversion of biomass resources. In this work, a group of Zr-doped CeO2 solid solutions were prepared and the defect chemistry in CeZrxOy (0.02 ≤ x ≤ 5) catalyst was elucidated over the oxidative coupling of lignin-based aniline and benzyl alcohol. Varying the Zr molar fraction enabled to successfully adjust the defect sites of catalysts and further influence their catalytic performances. In addition, the optimal CeZr1Oy catalyst exhibited a flexible temperature adaptability, wide substrate scope and superior reusability. Various characterizations, kinetic investigations, controlled experiments, DFT calculations and in situ DRIFT-IR technique were used to unravel the roles of Ce3+ and oxygen defects and the reaction mechanism. It was disclosed that Zr-doped defects can obviously increase surface Ce3+ cations, oxygen species (peroxide and superoxide anions) and oxygen vacancies. These coordinatively unsaturated sites were shown to play critical roles in absorbing and activating substrates hence can accelerate the formation rate of bio-based imines.

Enhancing Photocatalytic Activity, Stability, and Separability of TiO2 through Synthesis of Fe3O4@Fibroin‐TiO2 Composite

AbstractThis report uses a low‐cost and straightforward technique to synthesize a highly active, magnetically separable, and optically active nano‐biocomposite. The nanocomposite was created by combining Fibroin, TiO2, and Fe3O4. The analyses confirmed the formation of a core‐shell structure of Fibroin and Fe3O4, which was then combined with titanium dioxide nanoparticles. The incorporation of nanoparticles reduced the band gap of the system from 3.2 eV in bare titanium oxide to 1.8 eV. This enhancement improved its light absorption and charge generation. Additionally, the nano‐biocomposite showed improved chemical stability and photocatalytic activity when compared to bare TiO2 in the oxidation of benzyl alcohol under visible light (With 99 % yield and over 99 % selectivity). These results suggest that our nano‐biocomposite is a promising catalyst for photocatalytic applications under visible light.

Steering benzyl alcohol electrooxidation coupled with hydrogen evolution via hetero‐interface construction

AbstractIt is still a challenge to develop electrocatalyst for the efficient adsorption and conversion of organic molecule in aqueous media. Herein, a hetero‐interface structure based on CuO@Ni(OH)2 is rationally designed to enhance the performance of benzyl alcohol oxidation to benzoic acid. A high Faradaic efficiency of 99% and the yield of 3.09 mmol cm−2 h−1 are achieved at 1.70 V versus reversible hydrogen electrode, outperforming the previously reported electrocatalysts. Furthermore, a membrane‐free flow electrolyzer was assembled based on CuO@Ni(OH)2 hetero‐interface, exhibiting a much high yielding of benzoic acid (6.73 mmol cm−2 h−1) and hydrogen (0.35 L cm−2 h−1) with excellent stability. Both experimental data and density functional theory calculations verify that the electron is tend to accumulate at the hetero‐interface, thus accelerating the adsorption of reactant and intermediate and reducing the energy barrier of the conversion of benzyl alcohol to benzoic acid.

Surface engineering of biochar toward simultaneously generating superamphiphilicity and catalytic activity for strengthening Pickering interfacial catalysis.

Multifunctional carbon materials have revealed distinctive features and excellent performance in the field of catalysis. However, the facile fabrication of bifunctional carbon materials with special wettability and catalytic activity remains a grand challenge in Pickering emulsion catalysis. Herein, we reported one-step construction of bifunctional biochar with superamphiphilicity and catalytic activity directly from the thermolysis of sawdust and 1-butyl-3-methylimidazolium tetrafluoroborate for enhancing the oxidation of benzyl alcohol in Pickering emulsion. Co-doping of B and F enhanced the hydrophilicity of biochar, and the oleophilicity of biochar was kept simultaneously. Conversion became 4 times using bifunctional biochar compared with blank results during the oxidation of benzyl alcohol. More interestingly, the turnover frequency (TOF) value using bifunctional biochar enhanced 61% than that employing N-doped superamphiphilic carbon without catalytic activity. Catalytic activities of bifunctional biochar could be ascribed to the existence of different chemical bonds containing the element B. This work paves a path toward rational design of bifunctional biochar materials with special wettability and catalytic activity for greatly enhancing the liquid-liquid biphasic reaction efficiencies.

Hollow heterojunction with dual-vacancy engineering to boost photocatalytic performance for photoreduction of CO2 coupled with selective oxidation of benzyl alcohol to benzaldehyde

CO2 photoreduction into chemical fuels is hopeful and sustainable for a carbon–neutral future. Herein, a bifunctional dual-vacancy-modified hollow heterojunction photocatalyst is ingeniously designed for CO2 photoreduction to CO coupling with selective oxidation of benzyl alcohol to benzaldehyde. Synergistic catalysis effect resulted from hollow heterostructures, TiO2 with O vacancies (TiO2-x) and Zn0.3-xCd0.7S with Zn vacancies (ZCS) leads to excellent photoreduction and photoxidation performances. The optimized sample (TiO2-x/ZCS hollow sphere) exhibits highest photocatalytic activity of all the obtained samples. The yields of CO and benzaldehyde are 105 and 323.5 μmol g–1h−1, respectively. The construction of Z-scheme heterojunction realizes the spatial separation of redox reaction sites, and the dual-vacancy distributed on the heterojunction enhance the interfacial reactivity. Additionally, density functional theory calculation and in-situ technology reveal that Zn vacancy in ZCS and O vacancy in TiO2-x function as active sites for the binding and activation of *COOH and *PhCH2O-, respectively, thereby stabilizing the crucial step in the formation of intermediates such as CO and benzaldehyde. This work enhances the utilization of photogenerated carrier, and affords a new opportunity to design hollow heterojunction with dual-vacancy engineering to boost photocatalytic performance for coupling reaction system.

Towards lignin-based polyurethanes: a computational study of the influence of the reactants structure on the formation of urethanes in the presence of tin(II) dicarboxylate as a catalyst

An in-depth computational investigation of the tin-catalysed reaction of an alcohol with an isocyanate forming a urethane has been performed to elucidate the influence of the reactants, most importantly the type of alcohol or phenol, on its kinetics. The model alcohols were chosen based on those alcohol moieties present in lignin and comprised aliphatic, aromatic and benzylic alcohols, and reactions with both aliphatic and aromatic isocyanates were studied by modelling the rate-determining step of the urethane formation based on the mechanism proposed by Devendra et al. The results show that N-coordination is both kinetically and thermodynamically favoured for all reactions under consideration. Aliphatic alcohols react more readily than phenols with an aliphatic isocyanate, while benzylic alcohols react similarly to a bulky aliphatic alcohol. In the case of phenols, the kinetics are not influenced by the presence and/or number of ortho‑methoxy groups, but these will slightly alter the thermodynamics of the reaction. Aliphatic alcohols show slightly improved kinetics when reacting with an aromatic isocyanate, whereas phenols show no such preference. The reactions with the aliphatic isocyanate were also modelled in DMSO, but no significant changes in reaction kinetics were observed.

Preparation and Physicochemical Properties of a Thermosensitive Hydrogel-based Lipopeptide Biosurfactant

Background: Temperature-sensitive (thermo-sensitive) formulations are a novel drug delivery dosage form that shows bio-inspired behavior in various applications. The structure and properties of a thermosensitive polymer are critical in designing an intelligent biometric polymer that contains lipopeptide biosurfactants. Objectives: In this study, thermo-sensitive hydrogels with lipopeptide biosurfactants as a potential wound dressing dosage form were formulated and examined regarding physicochemical properties. Methods: The lipopeptide biosurfactants were isolated from the Acinetobacter junni B6 bacterial strain and loaded on a formulation of poloxamer 407® and carboxymethyl cellulose as a gelling agent. Numerous experiments were carried out to evaluate the physicochemical properties of these formulations, such as the stability, spreadability, release profile, and kinetic. Results: The formulation (Poloxamer 407® (19% w/v), carboxymethyl cellulose (2% w/v), lipopeptide biosurfactants (5mg/mL), benzyl alcohol (1% v/v), and 0.1mL polyethylene glycol 400) was select as the optimum formulation. The selected formulation released 26.9% of the lipopeptide biosurfactants with anomalous transport kinetics after 10 hours. Conclusions: The results showed that a thermo-sensitive formulation could help achieve a sustained release of lipopeptide biosurfactants and potentially be used as a dressing formulation for wounds in future studies.

Fabricating a Structured Single‐Atom Catalyst via High‐Resolution Photopolymerization 3D Printing

AbstractThis study introduces a novel solution to the design of structured catalysts, integrating single‐piece 3D printing with single‐atom catalysis. Structured catalysts are widely employed in industrial processes, as they provide optimal mass and heat transfer, leading to a more efficient use of catalytic materials. They are conventionally prepared using ceramic or metallic bodies, which are then washcoated and impregnated with catalytically active layers. However, this approach may lead to adhesion issues of the latter. By employing photopolymerization printing, a stable and active single‐atom catalyst is directly shaped into a stand‐alone, single‐piece structured material. The battery of characterization methods employed in the present study confirms the uniform distribution of catalytically active species and the structural integrity of the material. Computational fluid dynamics simulations are applied to demonstrate enhanced momentum transfer and light distribution within the structured body. The materials are finally evaluated in the continuous‐flow photocatalytic oxidation of benzyl alcohol to benzaldehyde, a relevant reaction to prepare biomass‐derived building blocks. The innovative approach reported herein to manufacture a structured single‐atom catalyst circumvents the complexities of traditional synthetic methods, offering scalability and efficiency improvements, and highlights the transformative role of 3D printing in catalysis engineering to revolutionize catalysts’ design.

Selective hydrodeoxygenation of 5-hydromethylfurfural to 2,5-dimethylfuran over PtFe/C catalyst

2,5-dimethylfuran (DMF), a promising biomass-derived fuel, is synthesized via the hydrodeoxygenation of 5-hydroxymethylfurfural (HMF). This study focuses on the inherent activity of a 5Pt5Fe/C catalyst for HMF hydrodeoxygenation to DMF. The catalyst exhibited exceptional performance, achieving a remarkable DMF yield of 99.6 %. It displayed specific selectivity for C = O bond hydrogenation and CO bond cleavage in diverse substrates, producing high yield of 2-methylfuran from furfural and furfury alcohol, and high yield of toluene from benzaldehyde, benzyl alcohol. In-depth characterizations unveiled valuable insights into the 5Pt5Fe/C catalyst's properties, emphasizing a harmonious balance between metal and acid sites due to the interactive synergy between Pt and Fe species, enhancing hydrodeoxygenation activity. Additionally, the catalyst demonstrated satisfactory stability, maintaining a commendable DMF yield over five reaction cycles despite observed changes.

Electrochemical oxidation of concentrated benzyl alcohol to high-purity benzaldehyde via superwetting organic-solid-water interfaces.

Organic electrosynthesis in aqueous media is presently hampered by the poor solubility of many organic reactants and thus low purity of liquid products in electrolytes. Using the electrooxidation of benzyl alcohol (BA) as a model reaction, we present a "sandwich-type" organic-solid-water (OSW) system, consisting of BA organic phase, KOH aqueous electrolyte, and porous anodes with Janus-like superwettability. The system allows independent diffusion of BA molecules from the organic phase to electrocatalytic active sites, enabling efficient electrooxidation of high-concentration BA to benzaldehyde (97% Faradaic efficiency at ~180 mA cm-2) with substantially reduced ohmic loss compared to conventional solid-liquid systems. The confined organic-water boundary within the electrode channels suppresses the interdiffusion of molecules and ions into the counterphase, thus preventing the hydration and overoxidation of benzaldehyde during long-term electrocatalysis. As a result, the direct production of high-purity benzaldehyde (91.7%) is achieved in a flow cell, showcasing the effectiveness of electrocatalysis over OSW interfaces for the one-step synthesis of high-purity organic compounds.

Nitrogen-Doped Porous Carbon Derived from Covalent Triazine Framework for Catalytic Oxidation of Benzyl Alcohol.

The catalytic oxidation of alcohols is an important transformation in the chemical industry. Carbon materials with a large surface area and N doping show great promise as metal-free catalysts for the reaction. In this study, a rich N-containing covalent triazine framework polymerized by cyanuric chloride and p-phenylenediamine was used to synthesize N-doped porous carbon with the assistance of a pore-forming agent-NaCl. First, the mass ratio of the polymer/NaCl was optimized to 1:9. Then, the influence of the pyrolysis temperatures (700-1000 °C) on the materials was studied in detail. It was found that the carbon materials were gradually exfoliated by molten salt at high temperatures. XRD and Raman characterizations showed them with a certain graphitization. The optimal doped carbon CNN-1-9-900 achieved the highest surface area of 199.03 m2g-1 with the largest pore volume of 0.29 cm3g-1. Furthermore, it had a high N content of 9.9 at% with the highest relative proportion of pyridinic/graphitic N. Due to the synergistic effect between the surface area and pyridinic/graphitic N, CNN-1-9-900 showed the best performance for benzyl alcohol oxidation with TBHP at moderate conditions, and the process also worked for its derivatives.

A facile route to synthesize β‐Ga2O3 nanoparticles from γ‐polymorph through a rapid microwave route and their optical properties

AbstractDue to the wide bandgap, monoclinic structure and thermodynamic stability, β‐polymorph form of Ga2O3 nanomaterials is well‐received for various applications. However, as the γ‐Ga2O3 is difficult to synthesize, less attention has been paid towards it and its conversion to β‐polymorph. This paper reports the single‐step synthesis of γ‐Ga2O3 using a microwave‐assisted procedure. In this regard, γ‐Ga2O3 powders are synthesized in minutes using benzyl alcohol as the solvent using gallium acetylacetone as the precursor. The XRD of the as‐prepared powders indicates the formation of the γ‐Ga2O3 phase, the very broad peaks indicative of the small crystallite size as confirmed by TEM. The γ‐Ga2O3 powders were annealed at different temperatures and the complete phase conversion of γ‐Ga2O3 phase to β‐Ga2O3 phase happens at 700 °C. The TEM analysis shows the crystallite size to be ≈10 nm for the annealed β‐Ga2O3 phase. The as‐prepared nanopowders show very weak luminescence under excitation and in contrast, a blue‐green emission is observed in case of annealed powders. This confirms the presented strategy as having the potential to use β‐Ga2O3 nanopowders for different optoelectronic applications.