Benzyl Alcohol Research Articles

A Green and Efficient Electrocatalytic Route for the Highly‐Selective Oxidation of C–H Bonds in Aromatics over 1D Co3O4‐Based Nanoarrays

Electrocatalytic oxidation of C‐H bonds in hydrocarbons represents an efficient and sustainable strategy for the synthesis of value‐added chemicals. Herein, a highly selective and continuous‐flow electrochemical oxidation process of toluene to various oxygenated products (benzyl alcohol, benzaldehyde, and benzyl acetate) is developed with the electrocatalytic membrane electrodes (ECMEs). The selectivity of target products can be manipulated via surface and interface engineering of Co3O4‐based electrocatalysts. We achieved a high benzaldehyde selectivity of 90% at a toluene conversion of 47.6% using 1D‐Co3O4 nanoneedles (NNs) loaded on a microfiltration (MF) titanium (Ti) membrane, i.e, Co3O4 NNs/Ti. In contrast, the main product shifted to benzyl alcohol with a selectivity of 90.1% at conversion of 32.1% after modifying MnO2 nanosheets (NSs) on Co3O4 NNs/Ti (Co3O4@MnO2/Ti) catalyst. Moreover, benzyl acetate product can be obtained with selectivity of 92% at a conversion of 58.5% at high current density (> 1.5mA cm‐2), demonstrating that the pathway of toluene oxidation is readily maneuvered. DFT results reveal that modifying MnO2 on Co3O4 optimizes the electron structure of Co3O4@MnO2/Ti and modulates the adsorption behavior of intermediate species. This work demonstrates a sustainable, and continuous‐flow process for precise control over production selectivity of value‐added oxygenated derivatives in electrochemical oxidation of aromatic hydrocarbons.

A Green and Efficient Electrocatalytic Route for the Highly-Selective Oxidation of C-H Bonds in Aromatics over 1D Co3O4-Based Nanoarrays.

Electrocatalytic oxidation of C-H bonds in hydrocarbons represents an efficient and sustainable strategy for the synthesis of value-added chemicals. Herein, a highly selective and continuous-flow electrochemical oxidation process of toluene to various oxygenated products (benzyl alcohol, benzaldehyde, and benzyl acetate) is developed with the electrocatalytic membrane electrodes (ECMEs). The selectivity of target products can be manipulated via surface and interface engineering of Co3O4-based electrocatalysts. We achieved a high benzaldehyde selectivity of 90% at a toluene conversion of 47.6% using 1D-Co3O4 nanoneedles (NNs) loaded on a microfiltration (MF) titanium (Ti) membrane, i.e, Co3O4 NNs/Ti. In contrast, the main product shifted to benzyl alcohol with a selectivity of 90.1% at conversion of 32.1% after modifying MnO2 nanosheets (NSs) on Co3O4 NNs/Ti (Co3O4@MnO2/Ti) catalyst. Moreover, benzyl acetate product can be obtained withselectivity of 92% at a conversion of 58.5% at high current density (> 1.5mA cm-2), demonstrating that the pathway of toluene oxidation is readily maneuvered. DFT results reveal that modifying MnO2 on Co3O4 optimizes the electron structure of Co3O4@MnO2/Ti and modulates the adsorption behavior of intermediate species. This work demonstrates a sustainable,and continuous-flow process for precise control over production selectivity of value-added oxygenated derivatives in electrochemical oxidation of aromatic hydrocarbons.

The Central Role of Oxo Clusters in Zirconium‐Based Esterification Catalysis

Oxo clusters are a unique link between oxide nanocrystals and Metal‐Organic Frameworks (MOFs), representing the limit of downscaling each of the respective crystals. Herein, the superior catalytic activity of clusters, compared to zirconium MOF UiO‐66 and nanocrystals is shown. Focus is on esterification reactions given their general importance in consumer products and the challenge of converting large substrates. Oxo clusters have a higher surface‐to‐volume ratio than nanocrystals, rendering them more active. For large substrates, for example, oleic acid, MOF UiO‐66 has negligible catalytic activity while clusters provide almost quantitative conversion, a fact we ascribe to limited diffusion of large substrates through the MOF pores. Clusters do not suffer from limited mass transfer and we also obtain high conversion in solvent‐free reactions with sterically hindered alcohols (hexanol, 2‐ethyl hexanol, benzyl alcohol, and neopentyl alcohol). The cluster catalyst can be recovered and shows identical activity when reused. The structural integrity of the cluster is confirmed using X‐ray total scattering and pair distribution function analysis. Moreover, when homogeneous zirconium alkoxides are used as catalysts, the same oxo cluster is retrieved, showing that oxo clusters are the active catalytic species, even in previously assumed homogeneously catalyzed reactions.

In-situ ‘X’ doped ‘GCN’ photocatalyst enables selective aldehyde synthesis via photo-oxidation of benzyl alcohol under ambient conditions

Photo-oxidative selective conversion of benzyl alcohols using graphitic carbon nitride (GCN) is a sustainable strategy for conventional metal-doped heterogeneous catalytic oxidation systems. Non-metal doped graphitic carbon nitride (a subclass of GCN) enhances its properties as an efficient photocatalyst for oxidation. These heteroatom non-metal dopants alter the optical energy gap and chemical and electronic properties of GCN, making it ideal for creating cost-effective, practical utility. So, herein, we designed heteroatoms (X = B, S, C) doped GCN photocatalysts derived from melamine (M) with different heteroatom ingredients and compared their activity in detail. Among these, the photo-oxidation of benzyl alcohol under blue LED by S-doped GCN (S-GCN) photocatalyst exhibits utmost higher photocatalytic activity than other heteroatoms doped GCN photocatalyst due to suitable band gap and slow photoinduced charge carriers recombination. The suitable energy gap with higher chemical stability is accountable for the substantial increase in the photocatalytic efficiency of S-GCN in the solar light responsive integrating reactions of oxidation of benzyl alcohol in aerobic conditions. Attaining an exceptional >99 % selectivity towards benzaldehyde (up to 5 cycles without significant loss of activity) marks a remarkable milestone. This opens up new possibilities for using these simple non-metal-doped photocatalysts in fine chemical synthesis.

Enhanced interfacial electric field via sulfur vacancies modified ZnIn2S4-Vs@NiIn2S4 S-scheme photocatalysts for simultaneous H2 evolution and benzyl alcohol oxidation

Designing and developing efficient photocatalysts for H2 evolution and simultaneous oxidation of benzyl alcohol (BA) in aqueous environments provides a cutting-edge strategy for green synthesis. Nevertheless, the photocatalysts suffer from the low photoconversion efficiency because of the sluggish dynamics and repaid recombination of photogenerated charge carriers, which hindering their widespread applications. To address the limitation, a multifunctionnal sulfur vacancies (SVs) modified ZIS-Vs@NIS S-scheme heterojunction with a strong interfacial electric field effect was synthesized to use photocatalytic H2 production and BA oxidation, simultaneously. Experimental analysis supports that the synergistic effect of SVs and S-scheme heterojunction engineering result in a suitable energy band structure alignment and larger Fermi level potential difference. Those factors can realize effective charge transfer and separation, and enhance the photocatalytic performance. As anticipated, ZIS-Vs@NIS exhibited a superior photocatalytic performance with H2 and benzaldehyde (BAD) yields up to 168.1 and 146.1 μmol under the simulated solar-light irradiation for 1.0 h, respectively, which are approximately 13.3 and 11.8 times higher than pristine ZIS. Moreover, the photocatalytic H2 evolution coupled with BA oxidative dehydrogenation mechanism via S-scheme heterojunction over ZIS-Vs@NIS is also demonstrated in detail.

Enhanced functionalization of superparamagnetic Fe3O4 nanoparticles for advanced drug enrichment and separation applications

Backgroundsuperparamagnetic ferroferric oxide (Fe3O4) nanoparticles can be extensively functionalized for applications in drug enrichment and separation. Their high magnetic responsiveness and controllable surface modification enable rapid drug enrichment and separation under external magnetic fields. This study aimed to enhance the application potential of superparamagnetic Fe3O4 nanoparticles in the field of drug enrichment and separation by functionalizing these nanoparticles to improve their biocompatibility and targeting capabilities.Methodssuperparamagnetic Fe3O4 nanoparticles functionalized with dopamine were synthesized using benzyl alcohol as the solvent and iron acetylacetonate as the precursor. The dopamine-functionalized superparamagnetic iron oxide nanoparticles were used to analyze protein enrichment and separation. Characterization of the nanoparticles was conducted, including analysis of particle size distribution, Zeta potential, and fluorescence spectra using a fluorescence spectrophotometer.Resultsthe Fe3O4 nanoparticles maintained high magnetism from the original material and exhibited uniform particle size distribution and stable Zeta potential. The saturation magnetization of dopamine-functionalized superparamagnetic Fe3O4 nanoparticles showed no significant difference compared to before coating, indicating minimal influence of dopamine on the internal magnetic core of the nanoparticles. The Fe3O4 nanoparticles demonstrated good biocompatibility and stability.Conclusionfunctionalization of superparamagnetic Fe3O4 nanoparticles significantly enhances their efficiency in drug enrichment and separation processes, suggesting broad applications in the pharmaceutical industry.

Impacts of Small SBA-15 Mesopores on Translation and Rotational Diffusion of Benzyl Alcohol.

Small SBA-15 pores can enhance the catalytic activity of gold catalysts in the selective oxidation of benzyl alcohol reaction. The goal of this work is to probe the impact of SBA-15 pores on the translational and rotational diffusion of the reactive species (e.g., benzyl alcohol). Herein, we demonstrate the use of nuclear magnetic resonance-based diffusion-ordered spectroscopy (DOSY) and T1 relaxation techniques to measure the translational and rotational diffusion coefficients of liquid benzyl alcohol molecules in three distinct environments: bulk, pore, and near-surface. The DOSY and T1 relaxation techniques render the routine diffusion measurements for liquid molecules confined in small pores possible. Furthermore, we measure the translational and rotational diffusion coefficients of benzyl alcohol molecules in the bulk, pore, and near-surface environments at varying temperatures. These measurements are then correlated via the Arrhenius equation to determine the activation energy associated with their translational (Et) and rotational (Er) diffusion. A higher activation energy suggests a more difficult diffusion process, while a lower activation energy implies a facile diffusion process. Our findings demonstrate that the ranking of Et follows the order of bulk (difficult) > near-surface > pore (easy), whereas the ranking of Er follows the order of pore (difficult) > bulk > near-surface (easy). This result suggests that the small SBA-15 pores can facilitate the translational diffusion but hinder the rotational diffusion of benzyl alcohol molecules.

Application of Response Surface Methodology for concentration of fluorosilicic acid by extraction technique with benzyl alcohol as extractant

As a kind of alternative of natural fluorinated minerals and raw material for producing anhydrous hydrogen fluoride, fluorosilicic acid has attracted more and more attention. In order to raise its utilization rate, dilute fluorosilicic acid solution coming from chemical enterprises needs to be concentrated. The extraction technology with benzyl alcohol as extraction agent was used to concentrating fluorosilicic acid aqueous solution. In order to determine the optimizing operation conditions of the extracting process, single - factor experiments were carried out to confirm the significant affecting factors and their operating range. Then the Response Surface Methodology (RSM) was conducted to accomplish regression of a nonlinear quadratic polynomial model to the experimental data and statistical analysis. Based on these studies, the optimal technical parameters of extracting process are acquired by optimization of the model using the Design-Expert 13 software. The statistical analysis for the fitting response surface quadratic equation model indicated that the model was reliable and accurate with very low p-values (<0.0001), the predicted values with the model equation had remarkable consistency in experimental data. By a great number of optimizations carried out with the Design Expert 13 software based on the fitting model equation, the optimal extractive processing conditions for concentrating fluorosilicic acid aqueous solution were obtained: the phase ratio 7, the extraction time 120.11 min and the extraction temperature 39.70 °C. The optimal concentration of fluorosilicic acid is 26.68 %. In order to increase the concentration of fluorosilicic acid, three-stage cross-current extraction for dilute fluorosilicic acid solution was carried out at the optimizing extracting conditions, 17.43 wt% fluorosilicic acid solution can be concentrated up to 37.46 wt%. The extractant-benzyl alcohol can be recovered with vacuum distillation and recovery rate reached up to 98 %.

Development of Two Synthetic Routes to 4‐(N‐Boc‐N‐methylaminomethyl)benzaldehyde: A Versatile Starting Material in Pharmaceutical Synthesis

AbstractTwo novel synthetic routes to 4‐(N‐Boc‐N‐methylaminomethyl)benzaldehyde, an important pharmaceutical starting material, were developed using terephthaloyl chloride and terephthalaldehyde. In the first approach, terephthaloyl chloride was converted to an ester amide. The treatment of the ester amide with LiAlH4 followed by protection of the resulting amine with tert‐butoxycarbonyl anhydride yielded the corresponding benzyl alcohol. The benzyl alcohol was oxidized to the aldehyde completing the first‐generation synthesis. The second approach utilized a one‐step protocol mono‐selective reductive amination of terephthalaldehyde with N‐Boc‐methylamine using chlorodimethylsilane. Both methods were scalable to 50 mmol and provided the desired aldehyde in a synthetically useful yield, demonstrating their practicality.

Construction of sulfur-chloride co-doped triazine/heptazine homojunction carbon nitride photocatalyst for simultaneous production of H2O2 and lignin C-C bond cleavage

Photocatalytic H2O2 production and cleavage of lignin C-C bonds is a typical strategy that follows sustainable development. Unfortunately, the photocatalytic efficiency of these two reactions still faces significant challenges. Herein, a carbon nitride photocatalyst (tri/hep-CN) with sulfur-chloride co-doped triazine and heptazine structures was synthesized. It was simultaneously used for photocatalytic H2O2 production and lignin C-C bond cleavage. In the air atmosphere, the yield of H2O2 reached 1171.9 μmol•g−1•h−1 after the addition of β-1 lignin model 1,2-diphenylethanol (Dpol) to the solvent. The yield of H2O2 increased by 20 times compared with no addition of Dpol. The lignin C-C bond in Dpol is also efficiently broken, producing benzaldehyde and benzyl alcohol. tri/hep-CN has excellent photogenerated carrier separation efficiency and positive valence potential, which improves the photocatalytic H2O2 production and lignin C-C bond cleavage performance. Notably, coupling photocatalytic H2O2 production with lignin C-C bond cleavage to fully use photogenerated electrons and holes is also very important to obtain outstanding photocatalytic performance. Mechanistic studies have shown that photocatalytic H2O2 production follows an indirect reaction mechanism. Meanwhile, the cleavage of lignin C-C bond follows the Cβ radical mechanism and the single electron transfer mechanism. This work is very instructive for simultaneous photocatalytic H2O2 production and lignin C-C bond cleavage studies.

Photocatalytic Direct Para‐Selective C−H Amination of Benzyl Alcohols: Selectivity Independent of Side Substituents

AbstractAminoarenes are important molecules for broad applications in nearly all modern industries that involve chemicals. Direct and site‐selective C−H bond amination of arenes provides the most efficient and convenient method to prepare aminoarenes. A main challenge is to selectively install the amino group (or other functional groups) to the distal para‐carbon of arenes (especially multi‐substituted arenes) during the C−H bond functionalization events. Herein, we address this problem by designing a new strategy via a sequential radical dearomatization/radical amination/rearomatization process for para‐selective amination of benzyl alcohols. The para‐selectivity of our reaction is completely independent of the electronic and steric properties of the other substituents of the arene substrates. Aminoarenes with many substituents (up to full substitution) and diverse substitution patterns, including those difficult to synthesize previously, could be readily prepared using our protocols. Further exploration of the current strategy shall lead to other challenging C−H functionalization of arenes.

Photocatalytic Direct Para-Selective C-H Amination of Benzyl Alcohols: Selectivity Independent of Side Substituents.

Aminoarenes are important molecules for broad applications in nearly all modern industries that involve chemicals. Direct and site-selective C-H bond amination of arenes provides the most efficient and convenient method to prepare aminoarenes. A main challenge is to selectively install the amino group (or other functional groups) to the distal para-carbon of arenes (especially multi-substituted arenes) during the C-H bond functionalization events. Herein, we address this problem by designing a new strategy via a sequential radical dearomatization/radical amination/rearomatization process for para-selective amination of benzyl alcohols. The para-selectivity of our reaction is completely independent of the electronic and steric properties of the other substituents of the arene substrates. Aminoarenes with many substituents (up to full substitution) and diverse substitution patterns, including those difficult to synthesize previously, could be readily prepared using our protocols. Further exploration of the current strategy shall lead to other challenging C-H functionalization of arenes.

Electrochemical Hydrogenation of Quinoline Enabled by Cu0‐Cu+ Dual Sites Coupled with Efficient Biomass Valorization in Aqueous Solution

AbstractThe hydrogenation of nitrogen‐containing heterocyclic precursors in aqueous medium is challenging, especially at ambient temperature and pressure. Electrochemical hydrogenation (ECH) of quinoline to 1,2,3,4‐tetrahydroquinoline (THQ) at mild conditions using water as the hydrogen source is demonstrated with splendid activity on a Cu‐based nonprecicous catalyst. The yield of THQ is up to ≈100% with ≈100% selectivity at −1.275 V vs Hg/HgO. The real active sites and key intermediates are deciphered, where the Lewis acid‐base sites on the heterointerface of Cu/Cu2O are beneficial to the quinoline adsorption in a dual‐site coordination configuration and water dissociation to afford H*. The presence of Cu0 plays a vital role in inhibiting the binding of H*, which ensures good Faradaic efficiency. In addition, a novel co‐production system by coupling benzyl alcohol oxidation at the anode is established, achieving dual benefits in both energy utilization efficiency and economic benefits.

Cobalt-Catalyzed Asymmetric Migratory Nozaki-Hiyama-Kishi Coupling.

Selective functionalization of ubiquitous C-H bonds based on 1,n-metal migration provides an attractive and sustainable route to access complex molecules from readily available precursors. Herein, we report a Co-catalyzed asymmetric reductive migratory Nozaki-Hiyama-Kishi (NHK) coupling between two readily available electrophiles, aryl (pseudo)halides and aldehydes, via an unprecedented through-space aryl-to-alkenyl 1,4-cobalt/hydride shift. The judicious choice of ligands is crucial for selectivity, leading to either ipso- or migratory NHK products with exquisite control of regio-, E/Z-, and enantioselectivity. Enabled by a ligand relay catalytic strategy, this platform has been further extended to aryl-to-aryl asymmetric migratory NHK coupling. These high-value NHK adducts, including α-chiral allylic alcohols and benzyl alcohols, are readily convertible to a variety of useful synthons.

Efficient hole extraction to reactive oxidation sites over a Co3O4/Cs3Sb2Br9 p-n heterojunction for enhanced benzylic C(sp3)-H bond oxidation

Photocatalytic selective oxidation of aromatic hydrocarbons plays an important role in the production of value-added chemicals. A key step in this process is the activation of C(sp3)-H bond by photogenerated holes. However, the inadequate hole generation and lack of surface adsorption-activation sites severely hinders the improvement in photocatalytic C-H bond oxidation. In particular, the random charge migration to the surface impedes the effective capture of holes by surface active sites to dissociate the C(sp3)-H bond. Here, we design and fabricate a Co3O4/Cs3Sb2Br9 p-n heterojunction that effectively addresses these challenges. The p-n heterojunction forms strong built-in electric fields (BEF) facilitating spatial charge separation. Holes are accumulated on Co3O4, while electrons are accumulated on Cs3Sb2Br9, thereby offering abundant active holes and electrons. Moreover, Co3O4 shows stronger adsorption and activation capacity for the C(sp³)-H bond, enabling the C(sp3)-H bond dissociation with low reaction energy barrier. Consequently, the holes are directionally extracted from photoactive Cs3Sb2Br9 to catalytically active Co3O4 under visible light irradiation, thereby accelerating the toluene oxidation. The optimized 5 % Co3O4/Cs3Sb2Br9 exhibits a benzyl aldehyde (BAD) evolution rate of 5044 μmol g−1 h−1 and a benzyl alcohol (BA) production rate of 1820 μmol g−1 h−1, which are 12 and 17 times higher than that of blank Cs3Sb2Br9, respectively.

Innovative UPLC technique for concurrent quantification of etofenamate and benzyl nicotinate in the presence of methylparaben and benzyl alcohol in their topical cream: Greens, white, and Six Sigma methodologies.

The efficacious treatment of muscle and joint pain relies heavily on etofenamate (ETO) and benzyl nicotinate (BN), which possess robust anti-inflammatory and pain-relieving properties when paired with methylparaben (MP) or benzyl alcohol (BA). In this study, we have established and validated innovative RP-UPLC methods for assessing ETO and BN in the presence of MP or BA in their dosage forms, employing eight green tools to evaluate their eco-friendliness and effectiveness. Reversed phase-ultra-performance liquid chromatography (RP-UPLC) technique employs a flow rate of 0.3mL/min on Waters Acquity UPLC BEH Column (C18, 1.7μm, 100 mm × 2.1mm), detection at 254 nm using a photo diode array (PDA) detector and mobile phase of 0.05 M KH2PO4 buffer, acetonitrile, and methanol (50:15:35, v/v/v) adjusted pH6.0 with 0.2% triethylamine. For ETO, BN, MP, and BA, the calibration curves were linear and ranged from 0.005 to 1.0, from 0.001 to 0.2, from 0.002 to 0.08, and from 0.0001 to 0.1mg/mL, respectively. The correlation value was 0.9999, and the accuracy findings ranged from 98.81% to 100.56%. Consequently, the methodology has been successfully implemented in assay testing for the pharmaceuticals in the presence of the MP or BA, demonstrating the high selectivity of these approaches. The present study presents the Blue Applicability Grade Index (BAGI), an innovative approach that complements green metrics in practical white analytical chemistry. According to the International Council for Harmonisation (ICH) criteria, the procedures were effectively validated.

Novel synthesis of vanadium phosphorus/ cerium promoted manganese oxide (VPO/Ce-OMS-2) nanocomposite as an efficient and selective catalyst for the aerobic oxidative coupling of benzyl alcohol and aniline to imine in the liquid phase

In this investigation, the VPO/Ce-OMS-2 composite was synthesized via the mechanochemical method and it was employed for the synthesis of imine in the liquid phase through a two-step process of oxidation of benzyl alcohol and subsequent condensation with aniline using air as an oxidant. The composite was synthesized with different mass ratios of (1:1), (1.5:1), (2:1) and (2.5:1). The effect of the VPO/Ce-OMS-2 mass ratio on catalyst activity has been investigated. As the mass ratio increases from (1:1) to (2:1), the benzyl alcohol conversion gradually increases, reaching 93% at a (2:1) mass ratio. Among the synthesized samples, the VPO/Ce-OMS-2(2:1) composite exhibited the highest selectivity towards imine formation and conversion of benzyl alcohol. Various techniques, such as XRD, FT-IR, BET, FESEM, EDX, DRS, NH3-TPD, and HRTEM, were utilized to characterize the catalysts. Results indicated that the composite synthesized with a (2:1) mass ratio has a favorable surface area, a mixture of micro-meso structures, and a high number of acidic sites, as confirmed by BET-BJH and NH3-TPD techniques. The DRS analysis demonstrated that the interaction between the two catalysts, VPO and Ce-OMS-2, enhances the selectivity for the desired product. The results clearly show the synergism effect in the combination of components VPO and Ce-OMS-2 and improving the activity and selectivity of the synthesized nanocomposite. The effects of reaction temperature, reaction time, solvents, VPO/Ce-OMS-2 mass ratio, catalyst amount, and reusability were studied. Recycling results for the VPO/Ce-OMS-2(2:1) composite show that the benzyl alcohol conversion decreases slightly after five cycles of use, and its stability is almost maintained. Optimizing the reaction conditions (0.2 g catalyst, VPO/Ce-OMS-2 mass ratio (2:1), solvent toluene, reaction temperature 90°C, and t = 8 h) resulted in a 93% conversion of benzyl alcohol with complete selectivity for the imine.

Designing 2D carbon dot nanoreactors for alcohol oxidation coupled with hydrogen evolution

The coupled green energy and chemical production by photocatalysis represents a promising sustainable pathway, which poses great challenges for the multifunction integration of catalytic systems. Here we show a promising green photocatalyst design using Cu-ZnIn2S4 nanosheets and carbon dots as building units, which enables the integration of reaction, mass transfer, and separation functions in the nano-space, mimicking a nanoreactor. This function integration results in great activity promotion for benzyl alcohol oxidation coupled H2 production, with H2/benzaldehyde production rates of 45.95/46.47 mmol g−1 h−1, 36.87 and 36.73 times to pure ZnIn2S4, respectively, owning to the enhanced charge accumulation and mass transfer according to in-situ spectroscopies and computational simulations of the built-in electrical field. Near-unity selectivity of benzaldehyde is achieved via the effective separation enabled by the Cu(II)-mediated conformation flipping of the intermediates and subsequent π-π conjugation. This work demonstrates an inspiring proof-of-concept nanoreactor design of photocatalysts for coupled sustainable systems.

A Facile Preparation of Tetrasubstituted Arylalkenes Catalyzed by p‐Toluenesulfonic Acid Monohydrate (p‐TsOH⋅H2O): Application in the Synthesis of the Intermediate of Tamoxifen

AbstractAn efficient synthesis of tetrasubstituted arylalkenes was readily achieved by the reaction of α‐(tert‐butyl)benzylic alcohols using p‐toluenensulfonic acid monohydrate as a Brønsted acid. A broad range of substrates was applicable for the reaction in good yield with high regioselectivity. The key intermediate in the synthesis of tamoxifen was produced using the present method as an example, and a plausible reaction mechanism was proposed by examining the reaction intermediates.

Controlled Ring-Opening Polymerization of Methyl Glycolide with Bifunctional Organocatalyst.

A bifunctional thiourea-amine-based organocatalyst (Takemoto's catalyst), employing a metal-free approach, is presented for the regioselective ring-opening polymerization (ROP) of optically active (D and L) methyl glycolide (MG). In this study, a chiral version of Takemoto's catalyst efficiently promotes the ROP of MG at room temperature, yielding poly(lactic-co-glycolic acids) (PLGAs) with predicted molecular weights and narrow polydispersity indices (PDI≤1.2). These PLGAs exhibit highly alternating structures without transesterification, as confirmed by 1H NMR, SEC, and MALDI-TOF analyses. Additionally, various macromolecular architectures, including linear and star-shaped PLGAs, were successfully synthesized using corresponding multi-functional alcohol initiators while maintaining the same alternating structures and regioselectivity with PLGA obtained from benzyl alcohol as initiator. Computational studies were conducted to elucidate the mechanism of alternating PLGA formation, revealing two key transition states (TSs): TS-1, which implicates the nucleophilic attack of the hydroxyl group of the initiator or propagating chain on the carbonyl carbon of MG, and TS-2, which involves the subsequent ring-opening of the cyclic ester. The results indicate that ring-opening occurs at both the glycolyl and lactyl sites, with a preference for the glycolyl site, as supported by experimental results. The resulting atactic PLGAs are amorphous, rendering them suitable for drug delivery applications.