Alkoxy Research Articles

Study of Butylated Hydroxytoluene Inhibiting the Coal Oxidation at Low Temperature: Combining Experiments and Quantum Chemical Calculations.

In order to cut off the chain reaction in the process of coal oxidation at low temperature (COLT), butylated hydroxytoluene (BHT) was used as an inhibitor to explore its inhibition effect and mechanism. In this paper, in situ Fourier transform infrared spectroscopy, electron paramagnetic resonance, and gas production of COLT experiments were conducted to compare the inhibited coal sample (BHT-Coal) with the raw coal. The results showed that BHT can effectively inhibit the formation of active free radicals, reduce the content of active alkoxy, carbonyl, and hydroxyl groups, increase the production temperature of CO, CO2, and C2H4, and reduce the concentration. The crossing point temperature increased from 132.3 to 157.4 °C, indicating that BHT can reduce the spontaneous combustion tendency of the raw coal. To explore the inhibition mechanism of BHT on COLT, five typical active free-radical models were established, and their active sites, active bonds, and thermodynamic parameters were calculated according to the density functional theory. The results showed that the highly active H atoms of the phenolic hydroxyl group in BHT can combine with active free radicals to generate stable compounds, and the activation energy of each reaction is small, which can occur under normal temperature and pressure. The inhibition mechanism of BHT is to reduce the concentration of the free radicals, so as to weaken the chain reaction strength during the COLT. This study provides a reference for the development and utilization of inhibitors.

Plasma-enabled synthesis of Pd/GO rich in oxygen-containing groups and defects for highly efficient 4-nitrophenol reduction

Effective catalytic removal of 4-nitrophenol (4-NP) in industrial wastewater remains a significant challenge due to the lack of highly efficient and stable catalysts. Herein, we demonstrated a promising plasma method for the facile, ultra-fast and low-temperature synthesis of graphite oxide (GO)-supported palladium catalyst (Pd/GO-P) rich in oxygen-containing groups (OCGs) and defects with smaller Pd nanoparticles (NPs) for highly efficient 4-NP reduction. The plasma method limited the damage to the OCGs and retained more OCGs (mainly alkoxy and hydroxyl groups) on the GO surface. In addition, plasma treatment can increase the active sites and the density of GO surface defects. These OCGs and defects promoted the 4-NP adsorption and improved the catalyst dispersion in the aqueous solution of 4-NP, thereby enhancing the catalytic reduction performance. The Pd/GO-P catalyst showed the highest reduction of 4-NP reported thus far, with a concentration-normalized rate constant of 5576 min−1 g−1 L. This value was 51.6 and 20.5 times greater than that using Pd/rGO-H prepared by a traditional thermal reduction method and a commercial Pd/AC catalyst, respectively. This work opens the avenue of exploring the use of plasma for the rational design of supported Pd catalysts with superior performance for the reduction and recycling of 4-NP in wastewater.

Influence of Different Substitution Patterns on the 2D Crystalline Aggregation of Small Molecules on HOPG Surfaces.

A series of benzoic and terephthalic acid derivatives and their corresponding ethyl esters have been synthesized. These are decorated with dendritic units carrying alkoxy chains that differ in the number of alkoxy groups and/or their substitution pattern. These molecules were deposited from solution on highly oriented pyrolytic graphite, and the resulting supramolecular surface patterns have been studied by scanning tunneling microscopy at the solid/liquid interface. Thus, we were able to perform a systematic study on the influence of orthogonal functional groups governing the supramolecular assembly, that is, the alkoxy chains of dendritic units and the carboxylic acid (ester) functions, on the intermolecular interactions, that is, van der Waals interactions and hydrogen bonding between the adsorbed species that drive the pattern formation.

Expanding Access to Optically Active Non-Steroidal Anti-Inflammatory Drugs via Lipase-Catalyzed KR of Racemic Acids Using Trialkyl Orthoesters as Irreversible Alkoxy Group Donors

Studies into the enzymatic kinetic resolution (EKR) of 2-arylpropanoic acids (‘profens’), as the active pharmaceutical ingredients (APIs) of blockbuster non-steroidal anti-inflammatory drugs (NSAIDs), by using various trialkyl orthoesters as irreversible alkoxy group donors in organic media, were performed. The enzymatic reactions of target substrates were optimized using several different immobilized preparations of lipase type B from the yeast Candida antarctica (CAL-B). The influence of crucial parameters, including the type of enzyme and alkoxy agent, as well as the nature of the organic co-solvent and time of the process on the conversion and enantioselectivity of the enzymatic kinetic resolution, is described. The optimal EKR procedure for the racemic profens consisted of a Novozym 435-STREM lipase preparation suspended in a mixture of 3 equiv of trimethyl or triethyl orthoacetate as alkoxy donor and toluene or n-hexane as co-solvent, depending on the employed racemic NSAIDs. The reported biocatalytic system provided optically active products with moderate-to-good enantioselectivity upon esterification lasting for 7–48 h, with most promising results in terms of enantiomeric purity of the pharmacologically active enantiomers of title APIs obtained on the analytical scale for: (S)-flurbiprofen (97% ee), (S)-ibuprofen (91% ee), (S)-ketoprofen (69% ee), and (S)-naproxen (63% ee), respectively. In turn, the employment of optimal conditions on a preparative-scale enabled us to obtain the (S)-enantiomers of: flurbiprofen in 28% yield and 97% ee, ibuprofen in 45% yield and 56% ee, (S)-ketoprofen in 23% yield and 69% ee, and naproxen in 42% yield and 57% ee, respectively. The devised method turned out to be inefficient toward racemic etodolac regardless of the lipase and alkoxy group donor used, proving that it is unsuitable for carboxylic acids possessing tertiary chiral centers.

Electroorganic Synthesis and Characterization of 4-Ethoxy Acetanilide using Platinum and Graphite as Anodes

Alkoxy group substituted compounds of acetanilide are found to have pharmacological and industrial importance. Synthesis of alkoxy substituted acetanilides via conventional thermal methods involves multi-step processes, formation of side products, and the poor yield of desired products. But, the vast literature studies reveal that electroorganic synthesis of alkoxy substituted acetanilide derivatives would be effectively carried out through electrochemical oxidation methods. The direct substitution of the ethoxy (alkoxy) group onto the aromatic ring, an electrophilic substitution, has not been attempted so far. This concept is taken as a preparatory attempt to find an alternative method to the tedious chemical route and to invent a direct method of introducing the ethoxy groups into the aromatic ring in a single step. A polarization study on acetanilide with ethanol as an electrolyte is carried out on platinum and graphite anodes to find out the oxidation potentials. Electrochemical ethoxylation of acetanilide at the platinum electrode is done by the Potentiostatic method using the oxidation potentials. The products are separated using preparative TLC and purified with suitable solvents. The products are characterized by UV, IR, NMR, and Mass spectra.

Design and self-catalytic mechanism of aluminum precursors bearing amino ligands for Al2S3 atomic layer deposition

As a unique nanotechnology, atomic layer deposition (ALD) has been extensively used for the preparation of various nanomaterials. An effective precursor is a prerequisite to ALD success. Herein, we designed and introduced alkyl, hydrogen, halide, alkoxy and amino ligands to aluminum precursors and investigated reaction mechanisms of Al2S3 ALD through density functional calculations. The results show that aluminum precursors with alkyl, hydrogen and halide ligands are kinetically disadvantageous and with alkoxy groups are thermodynamically unfavorable and Al precursors bearing amino groups are thermodynamically and kinetically favorable for Al2S3 ALD. The activity of trimethylaluminum (TMA) on the sulfydrylated surface is lower than that on the hydroxylated surface. The reaction barriers of the aluminum precursors bearing amino ligands on the sulfydrylated surface are obviously lower than that of TMA. Similarly, the barrier of the H2S reaction on the aminated surface is much lower than that on the methylated surface. All of the amino groups have a self-catalytic role and accelerate the reaction of Al2S3 ALD. These insights into aluminum precursors bearing amino ligands for Al2S3 ALD can provide theoreticalguidance for the discovery of new precursors and the ALD preparation of other aluminum and sulfur compounds.

Synthesis and Strong π-π Interaction of Hexaazatriphenylene Derivatives with Alternating Electron-Withdrawing and -Donating Groups.

Hexaazatriphenylene (HAT) derivatives have attracted wide attention because of their electron-deficient nature and unique self-assembly properties. In this work, a facile synthesis method for obtaining HAT derivatives with alternating electron-withdrawing nitrile and electron-donating alkoxy groups (HATCNOCn) is proposed. Crystal structure analysis indicated that HATCNOCn forms a one-dimensional columnar structure via strong π-π interactions. Density functional theory calculations revealed that the edge of HATCNOCn is divided into positively and negatively charged sites owing to the presence of alternating nitrile and alkoxy groups, which would induce strong π-π interactions. Thermal analysis and polarizing optical microscopy revealed that HATCNOCn exhibits columnar liquid-crystal phases. Time-resolved microwave conductivity measurements further demonstrated the photoconductive nature of HATCNOCn. The proposed strategy could provide a new strategy for the design of novel organic semiconductive materials.

Chemistry and Applications of Organosilanes – An Overview

Organofunctional silanes are hybrid materials of silanes having attracted greater attention since the last decade owing to its versatile properties and wide range of applications. In this review, we have summarized the types of organosilanes (RnSiX4-n), their reactions, and applications. Organosilanes usually have two reactive groups, organofunctional groups and hydrolyzable alkoxy groups, which undergo hydrolysis and condensation. Silanols (Si-OH) and siloxane (Si-O-Si) structures are formed by hydrolysis and condensation reactions, respectively. In general, organosilanes acts as excellent binding agent due to its bridging capacity through (Si-O-Si) bond linkage with metal surfaces. From the extensive literature survey carried out, we understand that the silanes are synthesized without comprehending the reaction kinetics mechanism. In the past few decades, significant advances were witnessed in the development of various organofunctional silanes, which were used in a wide range of research areas based on its bifunctional characteristics.

Synthesis and characterization of newly syringaldehyde based chalcone liquid crystals

In present study, two homologues series were synthesized based on chalconyl-ester and chalconyl-vinyl ester linking group. The mesomorphic properties of both calamitic-shaped homologues series were studied by polarized optical microscope and differential scanning calorimetry. In both series, SmC and nematic type mesophase pattern were observed with good temperature range and thermal stability. Further, the structure-property relationship has been studied for a better understanding about the effect of linking group on the mesogenic properties. The results indicate that the stability and type of the mesophase are dependent on the linking group with the addition of variable side alkoxy group on the terminal end group.

Distribution patterns and transportation behavior of alkylphenol polyethoxylate degradation metabolites among river, port area, and coastal water bodies of Kaohsiung City, Taiwan

In this study, we conducted a comprehensive study of the distribution, transportation behavior and potential ecological risk of alkylphenol polyethoxylates (APnEOs) in the aquatic environments of Kaohsiung City, Taiwan because little information is available regarding the fate of APnEOs in the water bodies of a total environment. At Love River, APnEOs concentrations were much higher at upstream of interception stations L15 (27.33 ± 1.22 μg/L) and L16 (6.31 ± 0.14 μg/L) than at downstream of interception stations L1–L14 (0.69–2.54 μg/L). Additionally, the average ethoxy (EO) chain lengths of APnEOs at L15 and L16 were longer than at L1–L14. These observations were attributed to the sluice between L14 and L15 that intercepts and accumulates untreated sewage from upstream areas and to the infrastructure of the sewage system that prevents domestic sewage from flowing downstream in the river and to the Kaohsiung Port Area. At Kaohsiung Port Area, APnEO concentrations ranging from 0.63 to 6.50 μg/L were measured. The concentration range and average EO chain length of these APnEOs were similar to those of the downstream stretch of the river, which was attributed to the mixing efficiency of the Kaohsiung Port Area and Love River through tidal exchange. At Cijin Coastal Area, APnEO concentrations ranged from 0.14 to 18.77 μg/L. Notably, the APnEO concentration of surface waters was much higher than that of bottom waters. This observation was attributed to the sewage discharged from the ocean outfall buoying up to the surface instead of mixing with surrounding bottom waters. In potential ecological risk, 19 of 39 sampling points exceeded toxic equivalency of 1 μg/L, and approximately 48.7% of the sampling points would exceed the threshold. The result provides insight into the environmental implications of APnEOs contamination in aquatic environments and useful information for environmental policy and ecological risk assessments.

Multi-site passivation-based antisolvent additive engineering with gradient distribution for superior triple cation P-I-N perovskite solar cells

The large number of diverse types of trap sites on the surface and inside perovskite substantially restrict the production of highly efficient and stable perovskite solar cells (PSCs). Therefore, it is essential to fabricate high-quality perovskite films via the passivation of multi-site defects at the surface and grain boundaries through modulating perovskite crystallization and passivating as many defects of perovskite films as possible. Although many passivation molecules have been reported, it is still necessary to develop a deeper understanding of the various functional group effects as well as the different passivation strategies that can be used to introduce additives. Here, to confirm the effects of functional groups, the four acrylate-based molecules that contain carbonyl (CO), hydroxyl (–OH), alkoxy (–O–CH2), or aromatic functional group are used as additives for antisolvent additive engineering (AAE). We then systematically investigate the effects of the passivation molecules on perovskite films and devices. The use of the optimum multi-functional additive, 3-Phenoxy-2-hydroxypropyl acrylate (PHA), enables a champion power conversion efficiency (PCE) of 20.72% as well as higher ambient air stability, as it retains over 51% of its initial PCE after 129 days. We also find that, compared to other representative passivation techniques, AAE containing passivation molecules leads to better perovskite films with a lower defect density and better photovoltaic performance. Consequently, the multi-type defects caused by the ionic properties of perovskite are substantially reduced due to the synergetic effects of the functional groups; further, the AAE approach has also proven to be a more promising way to obtain high-quality perovskite films corresponding to high-efficiency PSCs.

Enhancing the Intermolecular Interactions of Ladder-Type Heteroheptacene-Based Nonfullerene Acceptors for Efficient Polymer Solar Cells by Incorporating Asymmetric Side Chains

Enhancing the Intermolecular Interactions of Ladder-Type Heteroheptacene-Based Nonfullerene Acceptors for Efficient Polymer Solar Cells by Incorporating Asymmetric Side Chains

The alkoxylation effects on the excited‐state intramolecular proton transfer behaviors for 2,6‐bis(benzothiazolyl‐2‐yl)phenol fluorophore: A theoretical research

AbstractGiven the unique luminescent properties, the excited‐state intramolecular proton transfer (ESIPT) materials have attracted lots of eyes in recent years. In view of the promising highly efficient red‐emitting material, the 2,6‐bis(benzothiazolyl‐2‐yl)phenol (DBTP) under alkoxy groups at the 4‐position reveals important properties. In this work, modification of DBTP fluorophore, that is, DBTP‐OMe (methoxy), DBTP‐OEt (ethoxy), DBTP‐OPr (propoxy), and DBTP‐OBt (butoxy) derivatives, have been explored theoretically. Based on the analyses of chemical structural variations and infrared (IR) vibrational spectra in both S0 and S1 states, the enhanced intramolecular hydrogen bonding interactions could be clearly found, which will promote the ESIPT tendency. Particularly, the DBTP‐OMe with stronger hydrogen bond reveals the easier PT tendency upon photo‐induced excitation. Paying attention to the changes of highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO), it could be found the charge transfer happens in the excited‐state molecules, and the reorganization of charge densities should be conducive to promoting the ESIPT process. Simulated potential energy curves indicated the ultrafast ESIPT reaction occurs for DBTP‐OMe, DBTP‐OEt, DBTP‐OPr, and DBTP‐OBt derivatives. The searched transition state (TS) structures in S1‐state reaction path suggested the derivatives with few alkyl groups might be more probe to occur the ESIPT reaction than the more alkyl ones for DBTP system.

Facile prepared tropinone-based enone dyes with visible-light induced photothermal liquefaction and cold crystallization properties for reusable and switchable adhesive

The solid-liquid phase transition of adhesives triggered by two different wavelength light stimuli enables the switchable and reusable character. The adhesive which could be liquified by photothermal effect by single-wavelength light stimulus and solidified by natural cooling is much easier to operate but little developed. In this work, a class of tropinone-based enone dyes (TPs), prepared by one-pot Claisen-Schmidt condensation, were explored as a novel kind of single-wavelength light-switchable adhesives. TPs could absorption visible light and are non-fluorescent. By changing the length of alkoxy groups, the melting point and crystallization behavior were regulated. Especially, TP6 and TP8 could form overcooled liquid during the cooling process, thus enabling a proper adhesion operation window. Under 405 nm LED irradiation, the rapid solid-liquid transformation was achieved for some of TPs due to the high thermal conversion ability. TPs presented good adhesion strength toward glass plates. Among them, TP8 could work as a reusable and light-switchable adhesive.

Steric effect of di-lateral methyl substituent on the mesophase behavior of four-ring azo/ester/azo homologues

ABSTRACT Four series of azo/ester/azo four-rings homologues, namely, 4-substituted phenylazo-3-methyl phenyl-4′-n-alkoxy 3-methyl phenylazo benzoates (I n a-d), bearing two terminals substituents, the first is a compact polar group (X = methoxy, methyl, H and bromo) and the other terminal is an alkoxy group of varying chain length (n = 6 to 16), were prepared and their molecular structures confirmed. Their thermotropic behaviours were analysed with differential scanning calorimetry (DSC) and polarising optical microscopy (POM). TGA analysis revealed that the prepared materials are thermally stable within their mesophase temperature range. Irrespective of the polarity of X and/or the alkoxy chain length all compounds showed to display a nematic phase with high thermal stability and wide temperature range. The methoxy homologues showed to exhibit higher thermal stabilities. Comparing the nematic stability of the di-laterally dimethyl substituted (I n c) derivatives with X = CH3, with their previously reported mono-laterally methyl-substituted analogues (II n c) revealed that I nc homologues have thermal stabilities and mesophase temperature ranges lower than their corresponding analogues II n c. The effect of introducing the two lateral methyl groups on the extent of anisotropic polarisability of the whole molecule was discussed and their effect on the mesophase behaviour investigated. The photo-physical property was studied via UV-vis spectroscopy.

Synthesis and Performance Analysis of New Anionic–Nonionic Gemini Surfactants

Microwave-assisted method was used to synthesize successfully a series of new surfactants. Maleic anhydride, ethylenediamine, polyoxyethylene lauryl ether (number of polymerization of ethylene oxide = 3, 5, 7, 9, 12) and sodium sulfite were used. The optimal reaction conditions for synthesizing five new surfactant products were obtained by response surface design. The chemical structure of five new surfactant products were confirmed by Fourier transform infrared spectroscopy (FT-IR), mass spectrometry, elementary analysis and 1H-nuclear magnetic resonance (1H-NMR) analysis. The critical micelle concentration (CMC), surface tension, emulsifying power and foaming capacity in aqueous solution were studied. The microemulsion cutting fluid was also prepared by micro-emulsification of self-made new anionic–nonionic Genimi surfactant. The influence of the different structural unit of ethoxy (EO) and additives on the surface properties of five new prepared products was researched. CMC and γcmc of five new prepared products were in the scope of 3.39×10−4~3.48×10−4 mol/L and 21.9~23.4 mN/m respectively. Oxalamide polyoxyethylene(12) lauryl biether succinate sodium sulfonate was the optimum foamability and foam stability among five new prepared surfactants. Oxalamide polyoxyethylene( 3) lauryl biether succinate sodium sulfonate was the best emulsification power in the five new product. The cutting fluid prepared by self-made Gemini surfactant showed good performance. Experimental results show that it is expected to be a wide range applications in oil emulsification and other fields for new Gemini surfactants.

Novel Suberoylanilide Hydroxamic Acid Analogs Inhibit Angiogenesis and Induce Apoptosis in Breast Cancer Cells.

Histone deacetylases (HDACs) are the enzymes that catalyze the removal of the acetyl group from lysine residues and regulate several biological processes. Suberoylanilide hydroxamic acid (SAHA) is a notable HDAC inhibitor that exhibited remarkable anti-proliferative efficiency by alleviating gene regulation against solid and hematologic cancers. The aim of this study was to develop new chemotherapeutic agents for breast cancer treatment, therefore, a novel series of Suberoylanilide hydroxamic acid (SAHA) analogs were investigated as anticancer agents. We designed and synthesized a novel series of analogs derived from SAHA by substituting alkyl, alkoxy, halo, and benzyl groups at different positions of the phenyl ring. The newly synthesized analogs were assessed for their cytotoxic potential against four human cancer cell lines in comparison with healthy cell lines, using several biological assays. SAHA analogs displayed significant cytotoxic potential with IC50 values ranging from 1.6 to 19.2 μM in various tumor cell lines. Among these analogs, 2d (containing 3-chloro, 4-floro substitutions on phenyl moiety), 2h (containing 3,4-di chloro substitutions on phenyl moiety), and 2j (containing 4-chloro, 3-methyl substitutions on phenyl moiety) showed significant cytotoxic potential with IC50 values ranging from 1.6 to 1.8 μM in MCF-7 (breast carcinoma) cell line. More importantly, these analogs were found to be non-toxic towards healthy primary human hepatocytes (PHH) and mouse fibroblast cells (NIH3T3), which represent their tumor selectivity. These analogs were further analyzed for their effect on cell migration, BrdU incorporation, Annexin V-FITC and cell cycle arrest (Sub-G1 phase). Remarkably, analogs 2d, 2h, and 2j displayed significant HDAC inhibition than the parent SAHA molecule. Further studies also confirmed that these SAHA analogs are efficient in inducing apoptosis, as they regulated the expression of several proteins involved in mitochondrial or intrinsic apoptosis pathways. Findings in the Chick Chorioallantoic Membrane (CAM) assay studies revealed anti-angiogenic properties of the currently described SAHA analogs. From anti-proliferative study results, it is clearly evident that 3,4-substitution at the SAHA phenyl ring improves the anti-proliferative activity of SAHA. Based on these findings, we presume that the synthesized novel SAHA analogs could be potential therapeutic agents in treating breast cancer.

Effective adsorptive removal of dyes and heavy metal using graphene oxide based Pre-treated with NaOH / H2SO4 rubber seed shells synthetic graphite Precursor: Equilibrium Isotherm, kinetics and thermodynamic studies

Graphene oxide (GO) has excellent adsorption capacity as a promising adsorbent due to its large surface area consisting of large number of oxygen-functional groups. Nonetheless, the properties of GO are heavily influenced by the graphite sources and the type of pretreatment. This study aims to investigate the effect of pre-treatment of graphite sourced from agricultural wastes on the properties of the GO for the adsorption of dyes and heavy metal ion. Two sources of graphite (pre-treated with NaOH and H2SO4) were synthesised using biomass wastes (rubber seed shells) and were utlilized to produce high-efficiency GO for the adsorption of Methylene blue (MB), Congo red (CR) and Cadmium (II) from aqueous solutions. The effect of pre-treatment on the GO properties, behavior and performance was evaluated through batch adsorption studies which were conducted under operational condition of activation temperature (25–55 ○C), contact time (2–20 min), dosage (0.02–0.1 g), pH (2–12) using impregnation ratio of 1:4. The morphological analysis revealed that GO pretreated with NaOH (GO-N) graphite source exhibited more porous surface area compared to GO pretreated with H2SO4 (GO-H) graphite source, the surface properties was attributed to higher oxygen ratio as indicated in the EDX mapping and as demonstrated in the BET analysis. In general, both GO demonstrated excellent adsorption capacity due to their single-layered planes with noticeable functional groups which included hydroxyl, alkoxy, and carboxyl groups along with the π − π interactions and hydrogen bonds. Maximum monolayer adsorption capacities for the effective removal of CR, MB and Cd (II) was achieved as 299.38, 311.54, and 107.65 mg g−1 respectively onto GO-N compared to GO-H as illustrated by the Langmuir isotherms. Furthermore, the results showed that the experimental data were well-fitted to the pseudo-second-order model for both CR and MB including Cd (II) with GO-N with higher correlation coeficient R2 (R2 > 0.9) recorded. Thermodynamic study signified that the enthalpy (ΔH) and Gibbs free energy (ΔG) values of the adsorption process for both pollutants were negative indicating that adsorption of CR, MB and Cd were spontaneous and exothermic in nature which suggests that the adsorption of dyes and heavy metal from an aqueous solution was attributed to the presence of active sites and functional groups on the GO surface. However, the study revealed that GO–N proved to be a better adsorbent compared to GO-H under same operational condition and can be considered as a promising and cost-effective adsorbent for the removal of dyes and metal ions from industrial wastewater.

High‐Performance All‐Small‐Molecule Organic Solar Cells Enabled by Regio‐Isomerization of Noncovalently Conformational Locks

AbstractThe power conversion efficiencies (PCEs) of organic solar cells (OSCs) have surpassed 19% thanks to the innovation of polymer donors and molecular acceptors. However, the batch‐to‐batch variations in polymer materials are detrimental to the reproducibility of the device performance. In comparison, small‐molecule donors (SMDs) possess some unique advantages, such as well‐defined molecular weights, easy purification, and excellent batch‐to‐batch repeatability. Herein, a pair of regioisomeric SMDs (BT‐O1 and BT‐O2) has been synthesized with alkoxy groups as S···O noncovalently conformational locks (NoCLs) at the inner and outer position, respectively. Theoretical and experimental results reveal that the regioisomeric effect has a significant influence on the light‐harvest ability, energy levels, molecular geometries, internal reorganization energy, and packing behaviors for the two SMDs. As a result, BT‐O2‐based binary device shows an impressive PCE of 13.99%, much higher than that of BT‐O1 based one (4.07%), due to the better‐aligned energy level, more balanced charge transport, less charge recombination, lower energy loss, and more favorable phase separation. Furthermore, the fullerene derivative PC71BM is introduced into BT‐O2:H3 as the third component to achieve a notable PCE of 15.34% (certified 14.6%). Overall, this work reveals that NoCLs is a promising strategy to achieve high‐performance SMDs for all‐small‐molecule OSCs.

Synthesis, Structure-Activity Relationships, and Antiviral Profiling of 1-Heteroaryl-2-Alkoxyphenyl Analogs as Inhibitors of SARS-CoV-2 Replication.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, has led to a pandemic, that continues to be a huge public health burden. Despite the availability of vaccines, there is still a need for small-molecule antiviral drugs. In an effort to identify novel and drug-like hit matter that can be used for subsequent hit-to-lead optimization campaigns, we conducted a high-throughput screening of a 160 K compound library against SARS-CoV-2, yielding a 1-heteroaryl-2-alkoxyphenyl analog as a promising hit. Antiviral profiling revealed this compound was active against various beta-coronaviruses and preliminary mode-of-action experiments demonstrated that it interfered with viral entry. A systematic structure–activity relationship (SAR) study demonstrated that a 3- or 4-pyridyl moiety on the oxadiazole moiety is optimal, whereas the oxadiazole can be replaced by various other heteroaromatic cycles. In addition, the alkoxy group tolerates some structural diversity.