Benzyl Alcohol Research Articles

Evaluation of the Greenness, Whiteness, and blueness profiles of stability indicating HPLC method for determination of Denaverine hydrochloride and benzyl alcohol in pharmaceuticals

Recently, there has been important emphasis in pharmaceutical analysis on the stability of drug formulations and the development of appropriate stability-indicating studies. In this regard, a comprehensive stability-illustrating RP-HPLC approach has been established and validated for the assay of denaverine hydrochloride (DEN) and benzyl alcohol (BNZ) in Sensiblex® Injectable Solution.Different stress conditions were applied to both components, following the guidelines of the International Conference on Harmonization (ICH). Using the isocratic elution technique, DEN, BNZ, and their degradation products were effectively isolated and quantified on an Inertsil C8 column at room temperature. The mobile phase consisted of acetonitrile: water: orthophosphoric acid (80:20:0.1, by volume), and the flow speed was maintained at 0.8 mL/min. Detection was performed at 220 nm using a diode array detector, with concentration ranges of 10.00–30.00 and 5.00–15.00 μg/mL for DEN and BNZ, respectively. The total analysis time was less than five minutes, establishing this novel chromatographic method as a priority for routine quality control analysis of both drugs. The inclusion of acetonitrile was necessary for achieving adequate resolution. The environmental impact was evaluated using three approaches: Green Analytical Procedure Index (GAPI), Analytical Eco-Scale, and Analytical GREEnness metric (AGREE). Additionally, White Analytical Chemistry (WAC) was employed to evaluate the quality (R), ecological impact (G), and economic viability (B) of the developed approach.Additionally, the newly presented Blue Applicability Grade Index (BAGI) metric was also assessed. The final Eco-scale score of 85 and the AGREE score of 0.65 indicate the environmentally friendly nature of the new chromatographic method. The BAGI final score was 82.5, while the overall score of the WAC tool was 91.8, highlighting the method's practicality and utility. DEN exhibits the highest degradation (24%) in acidic conditions, whereas BNZ is particularly susceptible to oxidative degradation, with a degradation percentage of 35%. New four degradation products were formed, and the two investigated compounds were efficiently separated and analyzed in their presence. Further identification of degradation products for DEN and BNZ is strongly recommended, employing a mass spectrophotometric detector. Notably, the novel method is accurate, reliable, economical, and time-efficient. In conclusion, it can be effectively employed for routine quality control and stability assessment of DEN and BNZ in both their pure form and pharmaceutical formulations.

Influence of compatibilization methods on the compatibility between asphalt and DCLR components with molecular dynamics (MD) method

This study aims to investigate the effect of compatibilization methods on the compatibility between asphalt and direct coal liquefaction residue (DCLR) components to identify the key components in DCLR and asphalt that affect their compatibility. In this article, three types of compatibilizers, including benzyl alcohol (BA), dioctyl phthalate (DOP), and BA/DOP, were selected and acted on asphalt's components and DCLR's components, respectively. The molecular models of asphalt components, asphalt components with compatibilizers, DCLR components, and DCLR components with compatibilizers were established. The compatibility between DCLR and asphalt's four components, as well as between asphalt and DCLR's three components, were evaluated by solubility parameter difference (SPD) and interaction energy (IE). The compatibility between DCLR and asphalt was analyzed by Segregation test and Scanning Electron Microscope. Results indicate that the SPD and IE values between DCLR and asphalt components declined after adding compatibilizers, which implies that the repulsion decreased and the attraction increased between asphalt components and DCLR and the compatibility between asphalt components and DCLR improved. The IE values between DCLR components and asphalt increased after adding compatibilizers, which indicates that the compatibility was reduced between DCLR components and asphalt. The SPD values between DCLR components and asphalt increased after adding the BA/DOP. The SPD values between pre-asphaltene and asphalt decreased after adding the BA and DOP. The SPD value between asphaltene in DCLR and asphalt increased after adding the BA and decreased after adding the DOP. Moreover, the storage stability and homogeneity of DCLR-modified asphalt improved after adding compatibilizers, indicating that the compatibilizers enhanced compatibility between DCLR and asphalt. Finally, comparing the results of the tests, it could be found that compatibilizers preferentially acted on the asphalt components and mainly affected the aromatics in asphalt, thereby improving the compatibility between asphalt and DCLR. The effect of BA/DOP on improving the compatibility between asphalt and DCLR was better than that of BA and DOP.

Enhanced Co-adsorption of Alcohols and Amines for Visible Light Driven Oxidative Condensation Using Iron-based MOF.

Imines are essential intermediates in organic transformations, and is generally produced by dehydrogenative condensation of alcohols and amines with the assist of specialized catalysts and additives. Heterogeneous photocatalysis provides a sustainable platform for such process without the using of toxic oxidants, yet a functionalized photocatalyst with optimized co-adsorption of reactants needs to be developed to promote the stoichiometric oxidative condensation under ambient conditions. Here, we show that benzyl alcohol and aniline adsorb non-interferingly on the Fe node and the linker sites of the MIL-53(Fe) metal organic frameworks (MOFs), respectively. The co-adsorption of both reactants barely influences the reduction of molecular oxygen to generate oxygen radicals, resulting in efficient formation of benzaldehyde under visible light. Additionally, the weak adsorption of water together with surface acidity of the MIL-53(Fe) promote a rapid condensation of benzaldehyde with aniline and the depletion of generated water, achieving an efficient C-N bond creation for a wide range of substrates.

The Preparation of the Mn-Cr/SBA-15 Catalyst and its Ability to Selectively Oxidize Substituted Benzyl Alcohols

The Preparation of the Mn-Cr/SBA-15 Catalyst and its Ability to Selectively Oxidize Substituted Benzyl Alcohols

Impact of Ceria Support Morphology on Au Single‐Atom Catalysts for Benzyl Alcohol Selective Oxidation

AbstractAlcohol oxidations are a key industrial chemical transformation, with aldehydes and ketones finding use in an array of applications. Nobel metals are known for their activity towards this chemoselective transformation, however, sustainable catalyst synthesis requires optimal utilisation of these scarce elements. Here, we report Au catalytic systems based on the deposition of isolated Au sites on different morphologies of ceria in which different surface facets of the support are exposed. Through tailoring the support morphology and from extensive catalyst characterisation, it is shown that the exposed facet is critical for controlling the formation (or not) of isolated Au sites. Both the 110 and 111 facets are capable of this feat, yielding single‐atom sites for rod, octahedron, and polyhedron morphologies. In contrast, the 100 facet is not, resulting in Au nanoparticles on cubic ceria. This dictation over Au species is critical to benzyl alcohol oxidation capacity at mild conditions and in the absence of a soluble base, with only single‐atom catalyst (SAC) systems demonstrating activity. Furthermore, the exposed surface facet also governs the degree of surface oxygen vacancies, which is critical to catalyst activity due to their control over substrate adsorption strength, as revealed through T1/T2 NMR relaxation measurements.

Selective Oxidations of Toluenes and Benzyl Alcohols by an Unspecific Peroxygenase (UPO)

Unspecific Peroxygenases (UPOs) have emerged as robust biocatalysts for selective oxygenation reactions, as they are easily produced at scale and require only hydrogen peroxide as the external oxidant. UPOs can catalyze the oxygenation of the primary benzylic carbons of toluenes to give alcohol, aldehyde and carboxylic acid products. They can also catalyze hydroxylation at the benzylic position of ethylbenzenes, and the subsequent oxidation of the secondary alcohols to ketones. In this study, we have investigated factors that affect the balance of products in UPO‐catalyzed benzylic oxygenations using a range of functionalised toluenes and ethyl benzenes, and a UPO from Agrocybe aegerita (rAaeUPO‐PaDa‐I‐H variant). The product distribution is dependent upon a mixture of steric and electronic effects and, in selected cases, controlling the reaction conditions permits products from each product series to be generated chemoselectively. In this way, electron poor toluenes were converted directly into carboxylic acids in isolated yields of 36–99% on preparative scale.

Synthesis of Au–Pd@CeO2 nanocomposite as a potential catalyst for the Buchwald–Hartwig cross-coupling and amination of benzyl alcohol reactions

Synthesis of Au–Pd@CeO2 nanocomposite as a potential catalyst for the Buchwald–Hartwig cross-coupling and amination of benzyl alcohol reactions

Nickel-Doped Decatungstate as a Robust Photocatalyst for Violet Light-Triggered Redox Coupling Conversion of Alcohol and Water to Aldehyde/Ketone and Hydrogen.

The effective coupling of photoinduced alcohol oxidation and water reduction may economically produce hydrogen (H2) from water, which is of great significance in solving the current energy crisis. This study discloses that decatungstate (DT) and especially Ni2+ions-doped DTs are active for the photoreaction of benzyl alcohol with H2O, and under 48 h of violet light illumination, the best 1%Ni-DT yields ca. 86.1% benzoic acid and a 4.65 h-1 H2 generation efficiency (turnover frequency, TOF). Also, 1%Ni-DT is efficient for the photoredox coupling reaction of aliphatic and especially aromatic primary/secondary alcohols with water. A series of characterizations support that the doubled-reduced H2DT produced from the photoreaction plays a key role in water reduction to H2, which is accelerated by the doped Ni2+. In particular, it and the derived Ni3+ may construct a Z-type catalyst for water overall splitting, thereby hoisting the acid yield and H2 amount in the later stage of the photoreaction.

Fabrication of a New Platinum Electrode Modified with Bismuth Sulphide and Carbon Paste for Electrocatalytic Oxidation of Benzyl Alcohols in a Biphasic System

Fabrication of a New Platinum Electrode Modified with Bismuth Sulphide and Carbon Paste for Electrocatalytic Oxidation of Benzyl Alcohols in a Biphasic System

Defect‐Expedited Photocarrier Separation in Zn2In2S5 for High‐Efficiency Photocatalytic C─C Coupling Synchronized with H2 Liberation from Benzyl Alcohol

AbstractPhotocatalytic carbon‐carbon (C─C) coupling of benzyl alcohol is a promising means to coproduce the value‐added chemicals with H2 but is generally subject to low efficiency in terms of photon utilization. Here, efficient benzyl alcohol C─C coupling is achieved over Zn2In2S5 containing a tunable content of Zn vacancies (VZn). The VZn tends to form shallow defect states below the conduction band that can expedite photocarrier separation by collecting the photo‐generated electrons. The VZn‐collected electrons are essential for a high selectivity of the C─C coupling reactions because they enable a fast elimination of the byproduct benzaldehyde by catalyzing its reduction back to the ketyl radicals. Under simulated sunlight, the VZn‐containing Zn2In2S5 accomplishes ≈100% conversion of benzyl alcohol for merely 1 h and attains ≈100% selectivity for the C─C coupling compounds for 2 h, delivering an apparent quantum yield as high as 7.7% at 420 ± 20 nm. The benefits of VZn have also been verified by the theoretical calculations that indicate reduced energy barriers for various surface reactions in the presence of VZn. This work brings fresh mechanistic insights into the role of VZn and can serve as a useful guideline in the design of efficient photocatalysts.

Characterization of a Human Respiratory Mucosa Model to Study Odorant Metabolism.

Nasal xenobiotic metabolizing enzymes (XMEs) are important for the sense of smell because they influence odorant availability and quality. Since the major part of the human nasal cavity is lined by a respiratory mucosa, we hypothesized that this tissue contributed to nasal odorant metabolism through XME activity. Thus, we built human respiratory tissue models and characterized the XME profiles using single-cell RNA sequencing. We focused on the XMEs dicarbonyl and l-xylulose reductase, aldehyde dehydrogenase (ALDH) 1A1, and ALDH3A1, which play a role in food odorant metabolism. We demonstrated protein abundance and localization in the tissue models and showed the metabolic activity of the corresponding enzyme families by exposing the models to the odorants 3,4-hexandione and benzaldehyde. Using gas chromatography coupled with mass spectrometry, we observed, for example, a significantly higher formation of the corresponding metabolites 4-hydroxy-3-hexanone (39.03 ± 1.5%, p = 0.0022), benzyl alcohol (10.05 ± 0.88%, p = 0.0008), and benzoic acid (8.49 ± 0.57%, p = 0.0004) in odorant-treated tissue models compared to untreated controls (0 ± 0, 0.12 ± 0.12, and 0.18 ± 0.18%, respectively). This is the first study that reveals the XME profile of tissue-engineered human respiratory mucosa models and demonstrates their suitability to study nasal odorant metabolism.

Construction of 3D MoSx/Zn2In2S5 nanoflower heterojunction for boosted photothermal-assisted photocatalytic hydrogen evolution in biomass solution

Hydrogen production from solar energy conversion method is an attractive strategy to alleviate the energy crisis. The use of non-noble metal cocatalysts instead of noble metal monomers to improve the performance of photocatalytic hydrogen evolution reactions has been pursued by researchers. In this work, we develop a single-photon excited electron transport pathway system for photocatalytic hydrogen production performance studies by coupling 0D MoSx nanodots and 3D Zn2In2S5 nanoflowers. Experimental results combined with DFT calculations show that MoSx not only imparts photothermal properties to the composite material, but also acts as a conduit for electron transport, which can accelerate the rapid separation and transfer of photocatalytic charges. Among them, 3-MoSx/Zn2In2S5 selectively promoted photocatalyzed conversion of benzyl alcohol (BA, 100% conversion) into benzaldehyde (BAD, 96.82% selectivity) by simultaneous co-production of hydrogen (8.74 mmol•g−1•h−1) within 1 h, which is about 7.80 and 2.69 times higher than pure Zn2In2S5, respectively. Further, 3-MoSx/Zn2In2S5 can realize the hydrogen production reaction with glycerol as the substrate with a remarkable effect (up to 5.47 mmol•g−1•h−1). Additionally, 3-MoSx/Zn2In2S5 also showed some hydrogen production performance when other biomasses (glucose, xylose, and cellulose) were used as substrates. This work provides a feasible strategy for the design of photothermal photocatalysts for synergistic hydrogen production from biomass.

Ring-opening polymerization of six-membered cyclic hybrid dimers composed of an oxoester and thioester

AbstractThree cyclic oxoester-thioester hybrid monomers, 1 (3-methyl-1,4-oxathiane-2,5-dione), 2 (6-methyl-1,4-oxathiane-2,5-dione), and 3 (3,6-dimethyl-1,4-oxathiane-2,5-dione), were studied for anionic and cationic ring-opening polymerizations. These monomers are six-membered cyclic cross-dimers corresponding to combinations of glycolic and lactic acids with their thiol analogs. Anionic polymerizations using thiol as the initiator and 2,6-lutidine as the base catalyst were successful for the chemoselective cleavage of the thioester with the thiol propagating end. The polymerizability increased in the order of 3 < 1 < 2, which was in good agreement with the increasing ring strain order evaluated by Density Functional Theory calculations. The living character, to some extent, was suggested by the postpolymerization reactions, which involved a two-stage feed of the monomers and a thiol-ene terminal coupling reaction to form a block copolymer with PEG. Additionally, it was found that the polymerization took place in 2,6-lutidine without a thiol initiator and produced macrocyclic polymers. The cationic polymerizations took place with the aid of CF3SO3H and benzyl alcohol but involved side reactions with low chemoselective ring cleavage. The thioester unit caused the polymers to exhibit a lower Tg with greater thermal and photo degradability.

Mechanism of Electrocatalytic H2 Evolution, Carbonyl Hydrogenation, and Carbon-Carbon Coupling on Cu.

Aqueous-phase electrocatalytic hydrogenation of benzaldehyde on Cu leads not only to benzyl alcohol (the carbonyl hydrogenation product), but Cu also catalyzes carbon-carbon coupling to hydrobenzoin. In the absence of an organic substrate, H2 evolution proceeds via the Volmer-Tafel mechanism on Cu/C, with the Tafel step being rate-determining. In the presence of benzaldehyde, the catalyst surface is primarily covered with the organic substrate, while H* coverage is low. Mechanistically, the first H addition to the carbonyl O of an adsorbed benzaldehyde molecule leads to a surface-bound hydroxy intermediate. The hydroxy intermediate then undergoes a second and rate-determining H addition to its α-C to form benzyl alcohol. The H additions occur predominantly via the proton-coupled electron transfer mechanism. In a parallel reaction, the radical α-C of the hydroxy intermediate attacks the electrophilic carbonyl C of a physisorbed benzaldehyde molecule to form the C-C bond, which is rate-determining. The C-C coupling is accompanied by the protonation of the formed alkoxy radical intermediate, coupled with electron transfer from the surface of Cu, to form hydrobenzoin.

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.

Highly Selective Photooxidation of Benzyl Alcohol to Benzaldehyde by Bi–Mo/g-C3N4 in Aqueous Solution

Highly Selective Photooxidation of Benzyl Alcohol to Benzaldehyde by Bi–Mo/g-C₃N₄ in Aqueous Solution

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.