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The human alkylation B (AlkB) homologs, ALKBH2 and ALKBH3, respond to methylation damage to maintain genomic integrity and cellular viability. Both ALKBH2 and ALKBH3 are direct reversal repair enzymes that remove 1-methyladenine (1meA) and 3-methylcytosine (3meC) lesions commonly generated by alkylating chemotherapeutic agents. Thus, the existence of deficiencies in ALKBH proteins can be exploited in synergy with chemotherapy. In this study, we investigated possible interactions between ALKBH2 and ALKBH3 with other proteins that could alter damage response and discovered an interaction with the mismatch repair (MMR) system. To test whether the lack of active MMR impacts ALKBH2 and/or ALKBH3 response to methylating agents, we generated cells deficient in ALKBH2, ALKBH3, or both in addition to Mlh homolog 1 (MLH1), another MMR protein. We found that MLH1koALKBH3ko cells showed enhanced resistance toward SN1- and SN2-type methylating agents, whereas MLH1koALKBH2ko cells were only resistant to SN1-type methylating agents. Concomitant loss of ALKBH2 and ALKBH3 (ALKBH2ko3ko) rendered cells sensitive to SN1- and SN2-agents, but the additional loss of MLH1 enhanced resistance to both types of damage. We also showed that ALKBH2ko3ko cells have an ATR-dependent arrest at the G2/M checkpoint, increased apoptotic signaling, and replication fork stress in response to methylation. However, these responses were not observed with the loss of functional MLH1 in MLH1koALKBH2ko3ko cells. Finally, in MLH1koALKBH2ko3ko cells, we observed elevated mutant frequency in untreated and temozolomide treated cells. These results suggest that obtaining a more accurate prognosis of chemotherapeutic outcome requires information on the functionality of ALKBH2, ALKBH3, and MLH1. [ABSTRACT FROM AUTHOR]

In the Neurospora circadian system, the White Collar Complex (WCC) formed by WC-1 and WC-2 drives expression of the frequency (frq) gene whose product FRQ feedbacks to inhibit transcriptional activity of WCC. Phosphorylation of WCC has been extensively studied, but the extent and significance of other post-translational modifications (PTM) have been poorly studied. To this end, we used mass-spectrometry to study alkylation sites on WCC, resulting in discovery of nine acetylation sites. Mutagenesis analysis showed most of the acetylation events individually do not play important roles in period determination. Moreover, mutating all the lysines falling in either half of WC-1 or all the lysine residues in WC-2 to arginines did not abolish circadian rhythms. In addition, we also found nine mono-methylation sites on WC-1, but like acetylation, individual ablation of most of the monomethylation events did not result in a significant period change. Taken together, the data here suggest that acetylation or mono-methylation on WCC is not a determinant of the pace of the circadian feedback loop. The finding is consistent with a model in which repression of WCC’s circadian activity is mainly controlled by phosphorylation. Interestingly, light induced expression of some light-responsive genes has been modulated in certain wc-1 acetylation mutants, suggesting that WC-1 acetylation events differentially regulate light responses. [ABSTRACT FROM AUTHOR]

[Display omitted] High energetic compounds of pentanitroisowurtzitane series containing various polynitropyrazolyl substituents attached to the frame through a methylene linker were synthesized in two steps from the corresponding NH precursors and paraformaldehyde. The structures of the compounds obtained were characterized by spectral methods, and their energy characteristics were estimated. [ABSTRACT FROM AUTHOR]

[Display omitted] The alkylation of cyclic five-membered azomethine imines with carboxylic acids proceeds under irradiation with 400 nm light using a dual catalytic system consisting of 9-arylacridine and tetrabutylammonium decatungstate. Azomethine imines containing aromatic, heterocyclic and aliphatic groups are suitable for the process providing pyrazolidin-3-ones in 42–98% yields. [ABSTRACT FROM AUTHOR]

Activation of nuclear factor erythroid 2-related factor 2 (Nrf2) by Kelch-like ECH-associated protein 1 (Keap1) alkylation plays a central role in anti-inflammatory therapy. However, activators of Nrf2 through alkylation of Keap1-Kelch domain have not been identified. Deoxynyboquinone (DNQ) is a natural small molecule discovered from marine actinomycetes. The current study was designed to investigate the anti-inflammatory effects and molecular mechanisms of DNQ via alkylation of Keap1. DNQ exhibited significant anti-inflammatory properties both in vitro and in vivo. The pharmacophore responsible for the anti-inflammatory properties of DNQ was determined to be the α, β-unsaturated amides moieties by a chemical reaction between DNQ and N -acetylcysteine. DNQ exerted anti-inflammatory effects through activation of Nrf2/ARE pathway. Keap1 was demonstrated to be the direct target of DNQ and bound with DNQ through conjugate addition reaction involving alkylation. The specific alkylation site of DNQ on Keap1 for Nrf2 activation was elucidated with a synthesized probe in conjunction with liquid chromatography-tandem mass spectrometry. DNQ triggered the ubiquitination and subsequent degradation of Keap1 by alkylation of the cysteine residue 489 (Cys489) on Keap1-Kelch domain, ultimately enabling the activation of Nrf2. Our findings revealed that DNQ exhibited potent anti-inflammatory capacity through α, β-unsaturated amides moieties active group which specifically activated Nrf2 signal pathway via alkylation/ubiquitination of Keap1-Kelch domain, suggesting the potential values of targeting Cys489 on Keap1-Kelch domain by DNQ-like small molecules in inflammatory therapies. [Display omitted] • Small molecule DNQ exhibits potent anti-inflammatory effects via activation of Nrf2. • Target of DNQ was elucidated with a synthesized probe combined with Click Chemistry. • DNQ activates Nrf2 through alkylation and ubiquitination of Keap1-Kelch domain. • DNQ loses the anti-inflammatory capacity when site mutation of Keap1 at Cys489. [ABSTRACT FROM AUTHOR]

In a recent study in Nature Chemical Biology , Zheng et al. exploiting strain release by malolactone-based electrophiles designed a first-in-class covalent inhibitor that targets the elusive aspartate of the Kirsten rat sarcoma viral oncogene homolog (K-Ras)-G12D variant, which is highly prevalent in pancreatic cancer. The compound drastically inhibited oncogenic signaling and tumor growth in preclinical K-Ras-G12D-mutant pancreatic cancer models, expanding treatment potential beyond K-Ras-G12C-targeted therapies. In a recent study in Nature Chemical Biology , Zheng et al. exploiting strain release by malolactone-based electrophiles and designed a first-in-class covalent inhibitor that targets the elusive aspartate of the Kirsten rat sarcoma viral oncogene homolog (K-Ras)-G12D variant, which is highly prevalent in pancreatic cancer. The compound drastically inhibited oncogenic signaling and tumor growth in preclinical K-Ras-G12D-mutant pancreatic cancer models, expanding treatment potential beyond K-Ras-G12C-targeted therapies. [ABSTRACT FROM AUTHOR]

Aging-associated histone modification changes in oocytes have been sporadically reported, but the underlying mechanisms remain elusive. Here, we systematically characterize multiple histone modifications in oocytes during aging. We find that maternal and postovulatory aging markedly alter the status of histone modifications, specifically H4K12ac and H3K4me3, in both mouse and porcine oocytes. Meanwhile, we identify a substantial reduction in HDAC1 (histone deacetylase 1) protein in aged oocytes, which contributes to the changes in H4K12ac and H3K4me3. Moreover, by employing methylglyoxal (MG) and site-directed mutagenesis, we demonstrate that the elevated reactive carbonyl species (RCS) level induces HDAC1 degradation, likely through attacking the cysteine residues, thereby influences histone modification state. Importantly, supplementation of melatonin not only prevents the loss of HDAC1 protein, but also partially corrects the H4K12ac and H3K4me3 status in aged oocytes. To sum up, this study established the link between redox disequilibrium and histone modification alterations during mammalian oocyte aging. [Display omitted] • markedly alter the status of histone modifications, specifically H4K12ac and H3K4me3, in oocytes.Aging markedly alters the status of histone modifications. • Redox modulates the accumulation of HDAC1 in oocytes. • Melatonin supplementation ameliorates histone modification disorders and meiotic defects in mammalian aged oocytes. [ABSTRACT FROM AUTHOR]

[Display omitted] 3-[2-(Aminocarbonyl)pyridinium-1-yl]propane-1-sulfonate, a promising medicinal betain, was prepared by a one-pot synthesis with a 89% yield via N -alkylation of ethyl picolinate with 1,3-propanesultone in MeCN followed by ammonolysis. The reaction involving picolinamide in MeOH followed by the treatment with acetone afforded a novel 3,3-dimethyl- 1-oxo-2,3-dihydro-1 H -imidazo[1,5-a]pyridin-4-ium 3-methoxypropane-1-sulfonate. [ABSTRACT FROM AUTHOR]

[Display omitted] Diastereomeric P , S -bidentate phosphoramidite ligands with TADDOL core and (1 R ,2 S)-1,2-diphenyl-2-(phenylthio)-ethan-1-amine residue were synthesized. These ligands provided up to 76% ee in the Pd-catalyzed alkylation of (E)-1,3-diphenylallyl acetate with dimethyl malonate, up to 70% ee in the amination of this substrate with pyrrolidine, and 89–95% ee in the Rh-catalyzed asymmetric hydro- genation of dimethyl itaconate and methyl (Z)-2-acetamido-3-arylacrylates. The different contributions of diastereomeric chiral inducers to the catalytic outcome are discussed. [ABSTRACT FROM AUTHOR]

Low selectivity and complex product distribution are the main challenges for the utilization of lignin. Herein, the selective production of 2-(tert-butyl)-3-methylphenol (TBC), an antioxidant in the polymer industry, from depolymerization of enzymatic hydrolysis lignin (EHL) on a hydrothermally synthesized MoS 2 catalyst is studied. The total aromatic monomer yield is 124.1 mg/g EHL and the selectivity of TBC is up to 40.3 wt% in methanol at 280 °C under 2 MPa H 2 for 6 h. The FT-IR analysis of products reveals that MoS 2 has a high activity for demethylation, dehydroxylation and alkylation, and the dimer conversions reveal that C-O and C-C bonds in EHL are broken with MoS 2. The guaiacol and its derivants are identified as the intermediate for formation of TBC in EHL depolymerization according to the effect of time on product distribution and monomer conversion. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • High aromatics selectivity on ZnZrOx/ZSM-5 was observed by direct CO 2 hydrogenation. • Location and number of Brønsted acid sites were altered according to ZSM-5 morphology. • Nano-structured N-ZSM-5 was optimal for higher aromatics selectivity on hybrid catalyst. Direct synthesis of aromatics through CO 2 hydrogenation to oxygenates and its successive conversion to aromatics was investigated on hybridized ZnO-ZrO 2 metal oxides with ZSM-5. Hydrothermally synthesized micro-mesoporous ZSM-5 having four different morphologies with different Al distribution within ZSM-5 frameworks from small agglomerates to large elongated spherical particles such as nano (N-ZSM-5), hierarchically-structured hexagonal (H-ZSM-5), sheet-like (S-ZSM-5) and conventional cube-like (C-ZSM-5) structures. A larger number of strong Brønsted acid sites and small crystallite size of N-ZSM-5 in the hybridized ZnO-ZrO 2 /N-ZSM-5 were responsible for a largely enhanced CO 2 conversion of 22.9% and aromatics selectivity of 69.8% through methanol-to-aromatics reaction. The H-ZSM-5, having a larger number of external Brønsted acid sites, revealed a higher selectivity to alkylated tetramethyl benzene (TeMB) with 88.6% due to an enhanced surface C–C coupling reaction of aromatics formed from the tandem reaction. In addition, the selective distributions of Al species in the intersection micropores of sinusoidal and straight channels of the S-ZSM-5 showed an increased selectivity to xylene and trimethyl benzene (TriMB) and inhibited the formation of TeMB by further alkylation of surface intermediates through steric hinderance effects. The distributions of acidic sites and ZSM-5 morphology significantly altered local residence time resulted in different selectivity to aromatics and heavier hydrocarbons during gas-phase CO 2 conversion, which provided an efficient approach for direct CO 2 conversion to aromatics. [ABSTRACT FROM AUTHOR]

• Synthesis and Evaluation: Zn(II) mono- and Cu(II) binuclear salen complexes were synthesized and assessed for their catalytic performance in Cα-alkylation reactions. • Substituent Effects: Introducing a methoxy group at position 3 of the phenyl group in the salicylidene ligand significantly enhanced the asymmetric yield, while an allyl group reduced the yield. • Computational Insights: DFT calculations revealed that the improved performance with the methoxy substituent is likely due to increased stability of the binuclear complex during the transition state. • Dimeric Complex Advantage: A covalently cross-linked binuclear salen complex exhibited higher catalytic activity compared to mononuclear complexes, potentially due to enhanced intramolecular rigidity. • Future Directions: Further optimization of reaction conditions and exploration of different substrates and alkylating agents are suggested to enhance catalytic efficiency and versatility. Detailed mechanistic studies could aid in the rational design of more efficient chiral salen complexes for asymmetric catalysis. In this study, we present a series of Zn(II) mono- and Cu(II) binuclear salen complexes synthesized and assessed for their effectiveness in the Cα-alkylation reaction. Through systematic experimentation, it was observed that the introduction of a methoxy group at position 3 of the phenyl group in the salicylidene ligand led to a notable enhancement in asymmetric yield, while an allyl group reduced yield. Computational DFT calculations supported the involvement of the binuclear complex in the transition state of the reaction, elucidating the underlying mechanisms governing the observed catalytic behavior. A newly synthesized binuclear complex exhibited significantly higher catalytic activity compared to its mononuclear counterpart which could potentially be explained by increased intramolecular rigidity. This comprehensive investigation not only advances our understanding of structure-activity relationships in chiral salen complexes but also provides valuable insights for the rational design and optimization of catalysts for the asymmetric Cα-alkylation reaction. [Display omitted] [ABSTRACT FROM AUTHOR]

Proton exchange membrane (PEM) is an important component that affects the cost and cell performance of PEM water electrolysis (PEMWE). In this study, a series of ether-free poly(p -terphenyl-isatin- dimethylfluorene) (PID-x) polymers were synthesized by superacid-catalyzed Friedel-Crafts alkylation. The transparent PEMs of sulfonated poly(p -terphenyl-isatin- dimethylfluorene) (SPID-x) were prepared by the solution casting method. Introduction of dimethylfluorene groups enhances proton conductivity of PEMs while also preserving their high dimensional stability. The results indicate that the synthesized PID-x has excellent solubility in non-protic polar solvents. SPID-5, prepared with 5 % dimethylfluorene in the backbone structure exhibits a high conductivity of 0.176 S·cm−1 at 80 °C (compared to 0.155 S·cm−1 at 80 °C for Nafion115) and excellent dimensional stability, with a swelling ratio of only 10 % at 80 °C (compared to 20 % at 80 °C for Nafion115). In the water electrolysis cell performance test, SPID-25 achieved a current density of 167 mA·cm−2 at 2.5 V, outperforming the commercial Nafion 211 (151 mA·cm−2) at a similar membrane thickness. [Display omitted] • PEMs of sulfonated poly(p -terphenyl-isatin-dimethylfluorene) were synthesized and prepared. • The solubility of polymers has been enhanced by introducing dimethylfluorene. • Proton conductivity and dimensional stability have been improved through the introduction of a rigid structure. • SPID-25 exhibited a higher current density than Nafion 212 for electrolyzed water. [ABSTRACT FROM AUTHOR]

• Sequential olefin hydroboration/palladium-catalyzed alkyl suzuki coupling. • Easy access to ortho n -alkyl benzamides from anthranilic acid derivatives. • Readily available α-olefins as primary alkyl sources. • High primary alkyl selectivity. A denitrogenative alkylation of N -aryl benzotriazinones using readily available α-olefins as alkyl sources via a hydroboration/palladium-catalyzed alkyl Suzuki coupling sequence is reported to afford ortho n -alkyl benzamides in good to excellent yields. Scope and limitations of the sequential hydroboration/Suzuki coupling protocol have been explored, showing large steric effects of both benzotriazinone core and alkylboranes. Only primary alkyl group of trialkylboranes from anti -Markovnikov hydroboration of α-olefins could be effectively coupled, making the protocol highly selective for ortho n -alkyl benzamides. A highly selective hydroboration/palladium-catalyzed alkyl Suzuki coupling sequence is reported for efficient access to ortho n -alkyl secondary N -arylbenzamides from anthranilic acid derived 1,2,3-benzotriazinones under mild conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

The alkylation of tetrazole and acetone under the catalysis of TfOH has been shown to be an efficient process with high levels of regioselective control. This protocol features simple and readily accessible starting materials, unique reaction mechanism, excellent compatibility with diverse functional groups. [Display omitted] • An effective process with high-level regioselective control: alkylation reaction of tetrazole and acetone catalyzed by TfOH. • The raw materials of this scheme are simple and easy to obtain, the reaction mechanism is unique, and it has good compatibility with different functional groups. The alkylation of tetrazole and acetone under the catalysis of TfOH has been shown to be an efficient process with high levels of regioselective control. This protocol features simple and readily accessible starting materials, unique reaction mechanism, excellent compatibility with diverse functional groups. [ABSTRACT FROM AUTHOR]

[Display omitted] • The first visible-light induced dearomatization of biaryl ynones for the synthesis of alkylated spiro[5.5]trienones was developed. This tandem radical cyclization reaction represents a mild and environmentally friendly route using simple ethers as alkylation reagent. The novel and efficient work underwent tandem radical cyclization/dearomatization process with two new C C bonds and one C O bond formed. A visible-light-induced 6-exo-trig tandem cyclization dearomatization of biaryl ynones with simple ethers was developed. The reaction involves selective C(sp3) H bond cleavage and dual C C bond formation providing efficient, atom and step economical access to alkylated spiro[5.5]trienones under mild conditions. [ABSTRACT FROM AUTHOR]

• Enantioselective Friedel-Crafts of 1,3,5-trimethoxybenzene with trans - β -nitrostyrenes. • Species [Rh]- trans - β -nitrostyrene, [Rh]‑ aci -nitro and free aci ‑nitro have been characterised. • A plausible catalytic cycle based on [Rh]- trans - β -nitrostyrene, [Rh]‑ aci -nitro is proposed. The aqua complex (S Rh ,R C)-[Cp*Rh{(R)-Prophos}(H 2 O)][SbF 6 ] 2 (Prophos = propane-1,2-diyl-bis(diphenylphosphane) catalyses the asymmetric Friedel-Crafts (FC) alkylation of 1,3,5-trimethoxybenzene with trans-β -nitrostyrenes. Only the monoalkylated adduct was obtained in all cases with enantioselectivities of up to 93/7 e.r. Solution NMR measurements have allowed us to detect and characterise catalytic intermediates such as metal- trans - β -nitrostyrene and metal‑ aci -nitro complexes, as well as free aci ‑nitro compound. Based on these studies, a Michael-type Friedel-Crafts mechanism is proposed. The catalytic intermediates, [Rh]- trans - β -nitrostyrene, [Rh]‑ aci -nitro complexes together with the free aci ‑nitro compound have been spectroscopically characterised and have allowed us to propose a Michael-type Friedel-Crafts mechanism. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The yield of benzene alkylation can achieve 99% under the optimal process conditions. • The ionic liquid catalyst achieve continuous flow with slug flow pattern. • Industrial mixed olefins cause faster deactivation of ionic liquids compared to pure olefins. Alkylbenzene (LAB) is an important benzene derivative that can be used as a raw material for high-performance anionic surfactants such as alkylbenzene sulfonates (LAS) to meet the new requirements for surfactants in many fields. LAB can be synthesized through Friedel-Crafts reaction in the presence of acidic catalysts as alkylating agents, which is commonly used in the production of fine chemicals. In this work, a novel and efficient continuous flow micro reaction system was introduced to enhance the production of long-chain alkylbenzene catalyzed by [(CH 3) 3 NH][Al 2 Cl 7 ] ionic liquid. The optimal conditions were investigated for the synthesis of long-chain alkylbenzenes with the 1-tetradecene and mixing α-alkenes of C 14 -C 16 from Fischer-Tropsch process. The results showed that the yield of benzene alkylation can achieve 99 % under the optimal process conditions which the reaction tube length was 2000 mm, the reaction temperature was 30 ℃, the catalyst dosage was 0.30 mL/min and the molar ratio of aluminum chloride to trimethylamine hydrochloride was 2:1. In addition, α-alkenes with C 14 -C 16 lead to deactivation of the ionic liquids catalyst easier because of transfer of AlCl 3 from the ionic liquid to the organic phase compared to the pure 1-tetradecene as an alkylating agent. Continuous synthesis of the long-chain alkylbenzenes catalyzed by ionic liquids can achieve in the microchannel reaction system by controlling the flow patterns. [ABSTRACT FROM AUTHOR]

[Display omitted] • A synthetic route to novel high-energy–density biofuels from α-pinene. • Alkylation of α-pinene with lignin-based phenols followed by hydrodeoxygenation. • Potential biomass-based high-energy–density fuels with favorable properties. The present work investigated the alkylation performance of various lignin-based phenols as carbon-increasing blocks for α-pinene to create novel biomass-based high-energy–density fuels (HEDFs). H 3 PW 12 O 40 (HPW) was identified as an effective catalyst for the Friedel-Crafts alkylation of α-pinene and phenol substrates, with guaiacol showing the highest activity followed by phenol, anisole, 4-methylguaiacol, 4-ethylguaiacol, and 4-propylguaiacol. Moreover, guaiacol also displayed the best selectivity for monoalkylated products. Blended alkylated products of phenol, anisole, and guaiacol could be fully hydrodeoxygenated under the catalysis of HPW and Pd/C. However, the dialkylated components from 4-methylguaiacol, 4-ethylguaiacol, and 4-propylguaiacol were challenging to hydrodeoxygenation under the same conditions. After vacuum distillation, all refined products from different phenol substrates exhibited promising fuel properties, suggesting the potential for developing high-energy–density biofuels from α-pinene and lignin-based phenols using the approach outlined in this work. [ABSTRACT FROM AUTHOR]

New phthalimide substituted Ru(II)–NHC complexes have been synthesized, characterized, and investigated in the alkylation reaction of cyclic amines to synthesize valuable derivatives such as pyrrolidine and morpholine. [Display omitted] • High selectivity. • High yield. • Valued product. In this study, a series of benzimidazolium salts and silver-benimidazol-2-ylidene complexes were synthesized. The obtained silver complexes were converted into Ru(II)- benimidazol-2-ylidene complex using the transmetallation method. After elucidating the structures of these Ru(II)–NHC compounds, the synthesized ruthenium complexes were used in the alkylation reaction of cyclic amines to synthesize valuable derivatives such as pyrrolidine and morpholine. Pyrrolidine derivatives are extensively studied for their antimicrobial, antiviral, antifungal, anticancer, anti-inflammatory, anticonvulsant, cholinesterase inhibition, and carbonic anhydrase inhibition properties. Morpholine derivatives are particularly studied in the context of central nervous system (CNS) diseases. The yield of the catalytic products obtained was determined by GC. High selectivity and yield were achieved in the alkylation reactions of heterocyclic structures. [ABSTRACT FROM AUTHOR]

This work demonstrates that green aromatics can be obtained with high selectivity by the gas-phase upgrading of furfural using ZSM-5. Furfural suffers a fast decarbonylation and cracking, yielding monoaromatics (benzene, toluene, xylene, BTX) and naphthalenes. The low stability of this system is significantly enhanced by co-feeding light alcohols (biomass derived platforms), also increasing the selectivity of aromatics. Ethanol increases the BTX production (up to 36.4 % at 550ºC), whereas maximum naphthalene selectivity is 14.9 % at 450ºC. Using methanol strongly promotes the naphthalenes production (40.7 % at 450ºC), without affecting the BTX one, yielding global selectivities up to 70 %. The stability of the catalytic process increases with the temperature, whereas the alkylation grade must be modulated to prevent both, undesired condensations of non-alkylated derivatives, and diffuse restrictions of polyalkylated derivatives (promoted when using methanol). The optimum equilibrium between these two opposite effects is reached with furfural-ethanol, achieving a stability 3.7 times higher than the one obtained when feeding only furfural. These results represent a significant improvement over the existing literature, both from the activity/selectivity and the stability points of view, describing a promising sustainable route for obtaining aromatics. [Display omitted] • Acid-catalyzed furfural condensation considered for obtaining aromatics. • Catalyst deactivation is the main weakness of this approach. • Cofeeding light alcohols (ethanol and methanol) increases catalyst stability. • Ethanol cofeeding leads to increased BTX selectivities. • Methanol cofeeding promotes naphthalenes formation. [ABSTRACT FROM AUTHOR]

Chitosan exhibits moderate antimicrobial properties. Here, we enhanced the antimicrobial properties of chitosan through alkylation and chlorination and evaluated the effect of alkylation on chitosan's hydrophobicity, bacterial attachment, chlorination, biocidal property, and stability. First, chitosan films were prepared through casting and were then immersed in a hexanal solution of different concentrations. The aldehyde groups of hexanal reacted with the amino group in chitosan through a Schiff base reaction. Next, the hexanal-modified chitosan films were soaked in 10 % bleach to form N -halamine. The results demonstrated that the surface became more hydrophobic, and chitosan films with increased hexanal-grafting concentrations exhibited less bacterial attachment. However, the degree of chlorination decreased as the degree of alkylation increased, further reducing the diameter of the zone of inhibition. Nevertheless, all chlorinated samples could kill ~5 log of Staphylococcus aureus and Escherichia coli within 30 min. Unlike previous results for chlorinated chitosan, in this study, alkylation before chlorination enhanced antibacterial properties and bactericidal ability and decelerated the degradation of chlorinated samples. The results of a systematic evaluation indicated that a hexanal-grafting concentration of approximately 80 mM maintains the equilibrium of the various properties of chitosan. Alkylated and chlorinated chitosan has considerable potential application as mask filter layers. [ABSTRACT FROM AUTHOR]

The Cu-LDH@X composite materials were synthesized using the in-situ self-sacrificial template method, and the acid-base bifunctional Cs/Cu-LDO@X catalysts were prepared by impregnation-calcination. The as-synthesized catalysts were characterized by XRD, N 2 adsorption-desorption, SEM, HRTEM (EDS), FTIR, XPS, NH 3 -TPD, CO 2 -TPD techniques. The catalytic performance of the catalysts was evaluated in one step by implying a fixed-bed microreactor for the side-chain alkylation of toluene with methanol to styrene. The reaction mechanisms of the side-chain alkylation on the catalysts surface were deeply investigated. The Cs/Cu-LDO@X catalysts with adjustable acid-base sites and nanolayered structures demonstrated good catalytic performance for the side-chain alkylation of toluene. The Cs/Cu-LDO@X-3 catalyst exhibited the best catalytic performance with toluene conversion is up to 6.58%, while the selectivity of side-chain alkylated products and styrene is 91.64% and 54.16% respectively. The reaction mechanism investigation indicates that methanol dehydrogenated firstly to form formaldehyde under the action of the base sites on the catalyst surface, later, the adsorbed toluene on the acid sites underwent side-chain alkylation with formaldehyde. High selectivity of produced styrene owing to the synergistic interactions of acid-base sites and layered space-confined effects of the catalytic system. [Display omitted] • Synthesis of Cu-LDH@X composite materials by self-sacrificial template method. • Cs/Cu-LDO@X catalyst prepared by impregnation-calcination for styrene production. • Controllable acid-base properties in the catalysts enhanced catalytic performance. • Layered structure was beneficial to improve styrene selectivity. • Acid-base sites and layers space-confined effects play a synergistic role. [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]

Guaiacol ethanol alkylation (GEA), a model reaction of lignin solvolysis, has been intensively investigated. However, the product identification with gas chromatograph-mass spectrometer (GC-MS) was wrong due to the defect of the GC-MS databases. In this work, the main product was isolated with a flash chromatography technique and analyzed with 1H NMR and was identified as ethyl fully substituted phenol (or pentaethylphenol), which is contrary to the reported 2,6-di-tert-butyl-4-ethylphenol in previous literature. The NMR analysis of the entire product mixture further confirms that the product only contains ethyl substituted molecules, with no existence of isopropyl or tert-butyl substituted products. The byproducts, including ethyl partially substituted phenols, i.e., tetraethylphenol and triethylphenol, ethyl partially substituted guaiacol, 2-ethoxyphenol, and pentaethylbenzene, were also speculated based on the MS spectra. These findings rectify a long-standing error in product identification and may offer critical insights for mechanism investigations. [Display omitted] • Guaiacol ethanol alkylation (GEA) reaction was investigated. • Product identification solely based on GC-MS is not reliable. • The main product given by GC-MS 2,6-di-tert-butyl-4-ethylphenol is wrong. • Pentaethylphenol is the correct main product verified with 1H NMR. • Isopropyl and tert-butyl substituted phenols are not supported with HSQC NMR [ABSTRACT FROM AUTHOR]

Cannabinol (CBN), an oxidation product of THC, is a minor cannabinoid that displays a wide range of medicinal properties with less psychoactive effects. Traditionally, CBN derivatives are synthesized from terpenoids and resorcinol derivatives using a complex multistep process, involving Friedel-Crafts alkylation, cyclization, and aromatization. In this study, we propose that iodine could serve as both a Lewis acid catalyst and an aromatization agent. As a result, a convenient one-pot iodine-mediated reaction between (1 S ,4 R)- p -menthadienol and substituted resorcinol was developed. Various reaction parameters were explored, and the yields were assessed using quantitative 1H NMR. The optimized conditions gave a 71 % isolated yield of 3-(1′,1′-dimethylheptyl)cannabinol (DMH-CBN) as a model substrate. Further investigation of the substrate scope demonstrated that this one-pot iodine-mediated synthesis could provide alkyl-substituted CBN derivatives in isolated yields ranging from 28 % to 63 %, including the C3-unsubstituted CBN, which could undergo bromination to give novel 4-bromo and 2,4-dibromo derivatives in high yields. Citral was also successfully used in place of (1 S ,4 R)- p -menthadienol as an inexpensive alternative starting material to give the natural CBN in 22 %. These newly synthesized CBN derivatives were studied for their protective effects on the intestinal epithelial barrier using the transepithelial electrical resistance (TER) assay, suggesting that the 2,4-diethyl, 4-bromo, and 2,4-dibromo derivatives of C3-unsubstituted CBN exhibited superior activity compared to natural CBN with low toxicity. This indicates their potential as novel candidates in the cannabinoid series, contributing to the anti-inflammatory activity. [Display omitted] • A simple, one-pot synthesis of cannabinol (CBN) and derivatives was developed. • Iodine acts as both a Lewis acid catalyst and aromatizing agent. • CBN derivatives were synthesized in 1 h with isolated yields ranging from 28 % to 71 %. • New CBN derivatives were identified as potential anti-inflammatory candidates with low toxicity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Secondary benzylic and allylic trichloroacetimidates can alkylate 1,2,3-triazoles. • With acid catalysis the alkylation of 1,2,3-triazoles is N2-selective (up to 91:9 N2:N1). • This method gives access to N2-alkyl 1,2,3-triazoles which are useful in medicinal/materials chemistry. A Brønsted acid catalyzed alkylation method for 1,2,3-triazoles is described using trichloroacetimidates as the electrophiles. These conditions were selective, with a strong preference of N2 alkylation product, often in high yield. The ratio of N2:N1 alkylation is sensitive to both the type of solvent used and the reaction concentration. The optimal results were obtained with a non-polar solvent at higher dilutions. Both 1,2,3-triazoles and 1,2,3-benzotriazoles could be alkylated under these conditions, providing access to N2 substituted 1,2,3-triazoles in good yields. [ABSTRACT FROM AUTHOR]

Alkyl-thianthrenium salts-involved multicomponent reaction has been developed. The difunctionalization of olefins and C N coupling and could be realized simultaneously via this strategy. An oxidative radical/polar crossover may be contained in the mechanism. [Display omitted] • Photoredox : Photoredox is a rising method to achieve different chemical skeletons. • Difunctionalization of alkenes : Difunctionalization of alkenes could help install two functional units efficiently. • C N Coupling : Realizing the C N coupling via photoredox could help construct amine motifs. • Oxidative radical/polar crossover : bridging the gap between polar chemistry and radical chemistry. • Thianthrenium salts : economic substrates, and have never been used in multicomponent oxidative radical/polar crossover reactions. We reported an alkyl-thianthrenium salts (TTs) involved three-component radical alkene difunctionalization reaction. Alkylation of anilines has been realized via this mild method. An oxidative radical/polar crossover may be involved in the strategy, which realizing the combination of polar chemistry and radical chemistry. A variety of anilines, primary alkyl-substituted TTs, secondary alkyl-substituted TTs and olefins could be accessed in medium to good yield. Our work provides a valuable approach to producing diverse functionalized aniline derivatives. [ABSTRACT FROM AUTHOR]

An efficient Brønsted acid catalyzed formal (3 + 2) annulation reactions of 3-hydroxy-3-phenacyloxidole derivatives with 2-naphthols and activated phenols has been developed. This formal (3 + 2) annulation involved a dehydration/Friedel-Crafts alkylation/hemiketalization/dehydration cascade process, and afforded a variety of highly functionalized oxindolyl-naphthofurans with good yields. Moreover, some of the obtained products were tested against a panel of cancer cell lines, and one compound was identified to inhabit the proliferation of some cancer cell lines, thus indicating that such skeletons might server as leading compounds with antitumor activity. [Display omitted] • A formal (3 + 2) annulation reaction of 3-hydroxy-3-phenacyloxidole derivatives with 2-naphthols and activated phenols was established by the Brønsted acid catalyst. • This formal (3 + 2) annulation involved a dehydration/Friedel-Crafts alkylation/hemiketalization/dehydration cascade process, the strategy allowed the preparation of highly functionalized oxindolyl-naphthofuran scaffolds. • Moreover, we have done the bioactivity evaluation of the compounds, and one of the obtained products was identified to inhibit the proliferation of some cancer cell lines, thus indicating that such skeletons might serve as leading compounds for the development of antitumor drugs. • In situ construction of diverse oxindolyl-naphthofuran scaffolds with moderate to high yields. One of the products can inhibit the proliferation of some cancer cell lines. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZSM-12 with various morphologies and acidity were synthesized. • Acid distribution of ZSM-12 is crucial to the alkylation performance. • More Brønsted acid sites in channel are beneficial to the high selectivity to p -TBEB. Para - tert -butyl ethylbenzene (p -TBEB) is an important polymer monomer raw material to produce poly (tert -butylstyrene). Achieving relatively high selectivity to p -TBEB (S p -TBEB) by shape selective alkylation of ethylbenzene with isobutylene is highly attractive, and it is crucial to clarify the major factors affecting S p -TBEB. Herein, ZSM-12 zeolites with various morphology or acid distribution were synthesized by altering alkalinity or structure directing agent (SDA). Despite different morphology of MTW(70)-M- x series samples using MTEACl as the SDA, they show similar catalytic performance in alkylation of ethylbenzene with isobutylene due to their similar acid distribution. On the other hand, MTW(1 0 0)-M-0.06 and MTW(1 0 0)-T with various morphology, synthesized with MTEACl and TEAOH as the SDA, respectively, exhibit quite different selectivity to the target product in this reaction. MTW(1 0 0)-M-0.06 has much higher S TBEB (87 % vs. 70 %) and S p -TBEB (95 % vs. < 60 %) than MTW(1 0 0)-T, which is attributed to that MTW(1 0 0)-M-0.06 possesses much more Brønsted acid sites distributed in the micropore channel. This provides a route to improve the selectivity to main product (TBEB, especially p -TBEB) of alkylation of ethylbenzene with isobutylene over ZSM-12 zeolite even other zeolites. [ABSTRACT FROM AUTHOR]

[Display omitted] • In-situ B-Mg dual-modified ZSM-5 zeolite with complex is designed for alkylation of benzene and methanol. • Abundant and tunable weak Brønsted/Lewis acid sites by isomorphic substitution of B-Mg. • The side reactions of MTO and benzene alkylation with ethylene are inhibited by weak LAS. • 4 %Mg@B2-HZM-5 exhibited lowest EB selectivity (5.3 % in C8) and robust stability (240 h, 20 h−1). High-efficiency production of toluene and xylene from benzene-methanol alkylation is a potential way to optimize the resource structure between petrochemical and coal chemical industry. Herein, the porosity and acidity of ZSM-5 zeolite have been successfully tailored by in-situ Mg- and B-isomorphous substitution. UV–VIS–DRS, FT-IR, NH 3 -TPD and Py-IR characterizations unveiled that B and Mg isomorphous substitution in the framework of ZSM-5 and the detachment of Mg from the framework during calcination can enable the abundant weak Brønsted/Lewis acidic sites and the reduction of strong acidic sites. Thanks to the appropriate acidic density, types and strength to inhibit the alkylation of benzene and ethylene, as well as large mesopore to facilitate the mass transfer, the optimized 4 %Mg@B2-HZM-5 exhibits the excellent alkylation performance of benzene and methanol with a X B of 50.5 %, S T of 52.2 %, S C8 of 36.8 %, S C9+ of 11.0 %, Y EBinC8 of 5.3 %, and robust stability (240 h) at high WHSV (20 h−1). The possible mechanism on 4 %Mg@B2-HZM-5 for benzene alkylation with methanol was also further discussed. This work provides an efficient strategy to modulate the porosity and acidity via B and Mg isomorphous dual substitution to achieve an improved catalytic performance in benzene alkylation with methanol. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ni-containing phyllosilicate (Ni PS) was synthesized to get the Ni/Ni PS/HY. • Ni PS limited the deep hydrogenation of benzene on Ni. • The acidic sites in Ni PS provide adsorption sites for cyclohexene. • The mesoporous structure of Ni PS ensures the mass transfer of intermediates. The potential for synthesizing cyclohexylbenzene through one-step hydroalkylation of benzene is significant, but the selectivity is hindered by the deep hydrogenation of benzene to cyclohexane. In this study, Ni-containing phyllosilicate (Ni PS) was incorporated between Ni nanoparticles and zeolite (HY) using the deposition–precipitation technique, thereby creating Ni/Ni PS/HY. A conventional Ni/HY catalyst was also prepared using the impregnation method for comparison. Ni/Ni PS/HY demonstrates outstanding catalytic performance even at a low temperature of 130 °C and a high WHSV of up to 42.21 h−1, achieving a benzene conversion of ∼25 % and a cyclohexylbenzene selectivity of ∼85 %, which remained stable for 300 h. By contrast, the conventional Ni/HY catalyst yields a mere 2.5 % benzene conversion under identical conditions. Comprehensive characterizations and density functional theory (DFT) calculations reveal that Ni PS plays crucial roles in the hydroalkylation of benzene to cyclohexylbenzene. The formation of Ni PS leads to high Ni dispersion, generating more active sites for hydrogenation. Concurrently, the robust interaction between Ni PS and Ni reduces the reactivity of adsorbed H species, impeding the deep hydrogenation of benzene to cyclohexane, while still effectively allowing the formation of cyclohexene. After being adsorbed by the strong acid sites within Ni PS, the intermediate cyclohexene can be smoothly transported through the mesoporous structure of Ni PS to HY for alkylation. All these factors culminate in the exceptional catalytic performance of Ni/Ni-PS/HY. [ABSTRACT FROM AUTHOR]

• Microreaction strategy was realized to synthesize 1,3,5-triethoxy-2,4,6-trinitrobenzene. • Process parameters of alkylation process in batch reactor and microreactor were optimized. • Efficient and safe synthesis of TETNB in microreactors was achieved. • Kinetic models for the alkylation reaction were developed and validated. 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) is an essential insensitive energetic material. The alkylation of 1,3,5-trihydroxy-2,4,6-trinitrobenzene (Trinitrophloroglucinol, TNPG), which yields 1,3,5-triethoxy-2,4,6-trinitrobenzene (TETNB), is a pivotal step for the synthesis of TATB. The conventional synthetic process has suffered from long reaction time (∼165 min), intricate procedures, and intensive evaporation of a large number of volatile by-products, which increases the risk of spill and eruption of the reaction system, and necessitates in situ continuous gas–liquid separation. A new process for continuous alkylation in microreactors was proposed in this study. Firstly, a parametric investigation in the batch reactor was performed to explore the effects of various process parameters on the yields, resulting in the optimal experimental conditions, i.e., no reflux condensation, triethyl orthoformate (TEOF) as alkylation reagent, molar ratio of 12, reaction temperature of 120 °C and reaction time of 40 min. Subsequent continuous synthesis in microreactors was conducted, which realized the convenient process operation and no need of gas–liquid separation, leading to substantial improvement in the reaction efficiency and safety. Remarkably, within a packed microreactor, under the reaction temperature of 130 °C and residence time of 3 min, 99.24 % in the yield of TETNB was achieved. Comparing with conventional batch reactors, the required reaction time was reduced to approximately 1/50. Taking the advantages of precise control of temperature and reaction time in the microreactors, the kinetics of alkylation reaction were determined. This innovative approach of continuous synthesis can provide an efficient and alternative route for the synthesis of TATB, as well as other energetic materials and similar processes. [ABSTRACT FROM AUTHOR]

[Display omitted] The role of G-quadruplex (G4) in cellular processes can be investigated by the covalent modification of G4-DNA using alkylating reagents. Controllable alkylating reagents activated by external stimuli can react elegantly and selectively. Herein, we report a chemical activation system that can significantly boost the reaction rate of methylamine-protected vinyl-quinazolinone (VQ) derivative for the alkylation of G4‐DNA. The two screened activators can transform low-reactive VQ-NHR' to highly reactive intermediates following the Michael addition mechanism. This approach expands the toolbox of activable G4 alkylating reagents. [ABSTRACT FROM AUTHOR]

A series of Cs/CuAl-LDO@Al 2 O 3 @Fe 3 O 4 magnetic catalysts with varied CuAl-LDO contents were prepared by growing CuAl-LDH layers on the surface of Al 2 O 3 @Fe 3 O 4 magnetic cores, impregnated with Cs and followed by calcination. The as-synthesized catalysts were characterized by XRD, N 2 adsorption-desorption, SEM, TEM(EDS), XPS, NH 3 -TPD, CO 2 -TPD, and VSM techniques. The catalytic performance and reusability of the catalysts for the side-chain alkylation of toluene with formaldehyde were evaluated in a micro-high-pressure reactor, and the reaction mechanism was further studied. The results showed that the Al 2 O 3 @Fe 3 O 4 magnetic core of the catalyst was about 110 nm, and the CuAl-LDO formed a staggered lamellar structure with a shell thickness of around 30–45 nm. The magnetic catalyst demonstrated excellent catalytic performance and reusability for the side-chain alkylation of toluene with formaldehyde in one-step to styrene. As-synthesized magnetic Cs/CuAl-LDO@Al 2 O 3 @Fe 3 O 4 catalyst with CuAl-LDO content of 20 wt% delivered toluene conversion of 7.97% under optimized conditions, while the styrene selectivity and the selectivity of side-chain alkylation were 90.17% and 98.36%, respectively. The reaction mechanism showed that the benzene ring of toluene was stably adsorbed on the Al3+ acid sites of the CuAl-LDO layers. The C–H group of the side-chain of toluene formed carboanions and protons under the action of the Cuδ+–Oδ– base sites. Formaldehyde formed a transition state of adsorbed formaldehyde under the action of Cuδ+ acid sites. Finally, these adsorbed states and intermediate species accomplished the side-chain alkylation of toluene with formaldehyde to styrene in one-step under the synergic action of acid-base sites. The synergistic effects of suitable acid-base sites and lamellar spatial structures in the catalyst were the key to styrene formation with high selectivity. [Display omitted] • Synthesis of magnetic catalysts involves growing CuAl-LDH on Al 2 O 3 @Fe 3 O 4 and dipping Cs. • The acid-base properties of the magnetic catalysts were adjusted through calcination. • Satisfactory catalytic activity for side-chain alkylation of toluene in liquid-solid phase. • The rapid is separated by the applied magnetic field and can be reused continuously. • The acid-base sites and layered space-confined effects synergistically interact. [ABSTRACT FROM AUTHOR]

ZSM-5 monoliths with Si/Al ∼40 were achieved by steam assisted conversion of micro-/macroporous silica-alumina monoliths synthesized by an optimized combination of spinodal decomposition and sol-gel process. ZSM-5 monoliths exhibit a homogeneous and interconnected network of macropores of ∼30 μm diameter, with a macropore volume of ∼1 mL g−1 and a micropore volume of 0.16 mL g−1, as waited for pure ZSM-5. The skeleton of ZSM-5 monoliths featured a 3D aggregation of spherical particles of 6 μm in diameter. The latter were composed by a stacking of thin plate-like shaped crystallites. The catalytic properties of the ZSM-5 monoliths were assessed through their use as catalytic microreactor in the continuous flow alkylation of toluene with methanol. An outstanding for para -xylene selectivity of 81 % was achieved possibly ascribable due to the maximization of pore openings of sinusoidal channels as a result of the plate-like morphology of the ZSM-5 crystallites. [Display omitted] • Pseudomorphic transformation of aluminosilica monoliths. • ZSM-5 monoliths with hierarchical porosity for flow processes. • Large macropore diameter of 30–40 μm. • ZSM-5 with plate-like shape crystals. • High selectivity for para-xylene. [ABSTRACT FROM AUTHOR]

The pollution of water bodies by oil-containing compounds is increasing. Therefore, new oil-water separation adsorbents are under constant development. In this paper, melamine sponges with three-dimensional flexible porous framework are used to prepare oil-water separation adsorbents. Using a convenient one-step impregnation coating method, the material (THS@MS) was prepared by directly alkylating melamine sponge with a Trimethoxy (1 H, 1 H, 2 H, 2 H-heptadecafluordecyl) silane solution in an acidic (pH=5.5) ethanol solution. The adsorbent was superhydrophobic and had a strong oil adsorption capacity, ranging from 62.03 g/g to 71.33 g/g for various oils and organic compounds. After 50 cycles of oil-water separation, the separation efficiency remained above 95 %. The sponge remained in the superhydrophobic range after multiple separation tests. At this point, the hydrophobicity angle dropped by only a small value of 157.88 ° (compared to 158.57 ° in the original THS@MS test). THS@MS could be used to treat emulsion separations and is highly resistant to strong acid and alkali solutions. Its superhydrophobic properties enhanced self-cleaning ability and provided excellent environmental adaptability. The sponge showed great promise for wide application in real industries. [Display omitted] • THS@MS sponge was highly hydrophobic with a hydrophobicity angle of 158.57°. • THS@MS was highly self-cleaning and could easily separate waste oil in harsh environments. • THS@MS exhibited improved stability in acid, alkali, and compression tests. • THS@MS had strong oil-water separation capabilities and could successfully separate emulsions. [ABSTRACT FROM AUTHOR]

Catalytic N-alkylation is a frequently employed method to synthesize secondary amines and imines, yet selectivity control remains as a challenge that normally requires specialized catalysts under harsh reaction conditions. Here we propose a light-switchable N-alkylation of amines with aromatic halides for selective synthesis of secondary amines and imines, using an amine-functionalized metal-organic framework (MIL-125-NH 2) under mild conditions. The MIL-125-NH 2 catalyst possesses Lewis acidic sites, which catalyze direct dehalogenative condensation of bromides with primary amines to produce secondary amines in the dark. Upon irradiation, the MIL-125-NH 2 reduces molecular oxygen to create oxygen radicals, converting bromides into the corresponding aldehydes to yield imines via a dehydrative coupling with amines. With appropriate acidity, rapid oxygen reduction kinetics, and optimized adsorption of aromatic bromides and generated water, the system catalyzes the conversion of a wide range of substrates, thus featuring it a promising method for applications. [Display omitted] • Controlled selective cross coupling of aniline and bromides mediated by irradiation. • Lewis acidic sites on MOF boost dehalogenative condensation to yield amines in the dark. • Irradiation of the MOF activates oxidative debromination to yield imines. • The NH 2 -MOF shows proper acidity, fast oxygen reduction rates, and optimized adsorption of reactants. • A wide substrate scope for the light switchable N-alkylation process. [ABSTRACT FROM AUTHOR]

A novel organic small molecule, 5-(4-(diphenylamino)phenyl)-1-octylindoline-2,3-dione (TPI) containing an alkyl chain substituted electron accepting isatin (indoline-2,3-dione) and strong electron withdrawing N, N-diphenylaniline units have been synthesized through Suzuki coupling reaction. The molecular structure of TPI is confirmed by NMR, FT-IR, and Mass spectroscopy techniques. The TPI molecule exhibits a low band gap of approximately ∼ 2.03 eV which is also supported by the DFT results. The influence of additive and heat treatment on the electronic, morphological, and photovoltaic performance of organic solar cells was investigated meticulously. The TPI donor exhibits complementary light absorption with fullerene acceptor in combination with DIO and TA which efficiently absorb the photon in the 300–730 nm range. The TPI was later used as an electron donor material for the fabrication of organic solar cells. Remarkably, the morphology-dependent optimized TPI:PC 71 BM (1:3.0) exposed excellent power conversion efficiency (PCE) of about ∼ 5.56 % with enhanced V OC of ∼ 0.811 V, J SC of 11.81 mA cm−2 and FF of 55.3 % fabricated in addition with DIO and thermal annealing treatment. Most importantly, the unencapsulated devices maintained > 96 % of the initial PCE value after 240 h under ambient temperature. Our findings indicate that isatin-derived small molecules with simple architecture propose great potential for promising BHJ-OSCs material. [Display omitted] • A new D–A type small molecule donor TPI was prepared as efficient material for organic solar cells (OSCs). • The electron-rich isatin and electron-donating triphenylamine (TPA) unit in the TPI improved crystallinity and charge transport in the active layer. • The influence of DIO additive and thermal annealing treatment on the OSCs performance was investigated. • The fabricated devices express PCE of ∼ 5.56 % with improved photovoltaic parameters and room temperature stability. [ABSTRACT FROM AUTHOR]

Core-shell ZSM-5@Silicalite-1 presents high para-selectivity in the alkylation reactions, however, its industrial application faces great challenges due to the lack of the efficient strategy for large-scale synthesis. In this work, we proposed a silicon twice-release synthesis route to prepare ZSM-5@Silicalite-1 and the corresponding H-type extruded catalyst can be acquired after sequential filtration, heating, extrusion, and calcination. Almost all aluminum (Al) sites were consumed after the initial hydrothermal crystallization with a partial silicon, hence, a further crystallization with remaining silicon led to a siliceous shell as evidenced by the TOF-SIMS characterization. Adding nano Silicalite-1 seed was demonstrated to be the key point for the crystal epitaxial growth during the silicon twice-release synthesis route. With the increase of silicon proportion in the second release, the selectivity of para -ethyltoluene presented a volcano-type variation trend with a maximum of 92.6 % and a minimum of 66.5 %; while the catalytic stability obviously decreased when the proportion was larger than 50 % ascribed to the poor accessibility of active sites. This work provides a facile protocol to prepare core-shell catalysts, which promotes their large-scale production and industrial application. [Display omitted] • A seed-directed silicon twice-release route was developed to prepare ZSM-5@Silicalite-1. • Adding minimal nano seed was the key role to avoid independence nucleation and growth. • The thickness of Silicalite-1 shell can be regulated by changing the Si feeding ratio. • A high para -ethyltoluene selectivity of 92.6 % can be acquired over the optimal catalyst. [ABSTRACT FROM AUTHOR]

β-Pinene, unlike α-pinene, is easily and quantitatively metalated with butyllithium/TMEDA. The resulting allyllithium•TMEDA is easily isolated, with the racemic material crystallizing preferentially, even from 92 % ee solutions. The complex is indefinitely stable in C 6 D 6 , and has been fully characterized. Reaction with formaldehyde favors alkylation at the less substituted allyl position with modest regioselectivity (2:1), and the corresponding Grignard reagent (made by transmetalation with MgBr 2) reacts very regioselectively at the more substituted position with formaldehyde and diphenyl disulfide (99-92 %, resp.). The two phenyl sulfide isomers are observed to equilibrate when exposed to heat or UV light. This easy metalation provides access to a versatile chiral-pool-derived allyl nucleophile. [Display omitted] • Readily accessible chiral (92 % ee) allylmetallic. • Dramatic regiochemical outcomes between Li and MgX. • Unexpected equilibration of allyl phenyl sulfide regioisomers. [ABSTRACT FROM AUTHOR]

The chiral pool material carvone available in both enantiomer forms have been extensively used in total syntheses of various natural products. Different strategies have been developed considering the available structural features in both the enantiomers of carvone. The enone present has been remarkably used for epoxidation, conjugate addition, γ-oxygenation, reductive alkylation, etc. The six-membered ring has been contracted for arriving at the functionalized 5-membered ring moiety present in many natural products. Further, the carvone skeleton has been readily modified to advanced intermediates available for Friedel-Crafts alkylation, annulations, coupling reactions, metathesis and both inter- and intramolecular cyclizations. This review focused on various strategies developed using the carvone scaffold in total syntheses of different natural products in the period 2016 to 2023. [Display omitted] [ABSTRACT FROM AUTHOR]

A method for synthesizing polycyclic quinazolinone derivatives with ketoalkyl substitutions has been developed through strong acid-catalyzed radical tandem alkylation/cyclization of unactivated alkenes with readily available ketones under microwave irradiation. The transformation offers several advantages, including wide functional group compatibility, operational simplicity, and moderate to good yields. This methodology offers an appealing approach to obtaining keto-containing polycyclic quinazolinones with pharmaceutical value. [Display omitted] A method for synthesizing polycyclic quinazolinone derivatives with ketoalkyl substitutions has been developed through strong acid-catalyzed radical tandem alkylation/cyclization of unactivated alkenes with readily available ketones under microwave irradiation. The mechanistic studies revealed that the strong acid-catalyzed tandem alkylation/cyclization occurs through a radical pathway. This approach provides a potential route for the functionalization of quinazolinones that may find wide applications in pharmaceutical preparation. [ABSTRACT FROM AUTHOR]

As a green and efficient antioxidant, nonylated diphenylamine (NDPA) is of great significance to fields such as lubricants, synthetic rubber, and plastic. However, traditional catalysts for synthesizing NDPA still exhibit drawbacks of low efficiency, equipment corrosion, non-renewability, and environmental pollution. To overcome these challenges, a series of Fe-promoted SO 4 2-/ZrO 2 catalysts were successfully developed and employed for the first time in the alkylation of DPA and NON to synthesize NDPA in our present work. Both synthesis variables of catalysts and reaction conditions were well optimized. The as-synthesized NFe 2.50 S 1.0 Z catalyst possessed excellent catalytic performance with a high yield of mono- and di-nonyl-diphenylamine, as well as better reusability and stability than activated clay. After 5 reaction cycles, over 90 % of the catalytic activity could be recovered by the thermal treatment. These observations make the Fe-promoted SO 4 2-/ZrO 2 catalyst a promising candidate for industrials. Additionally, to systematically investigate and elucidate the promoting effects of Fe on sulfated zirconia catalysts, a thorough characterization of the physicochemical properties of these catalysts was conducted through various techniques, including XRD, SEM, TEM equipped with EDX, N 2 adsorption-desorption isotherms, EA, ICP-OES, FT-IR, XPS, and NH 3 -TPD. The results indicated that the introduction of a small amount of Fe into the catalyst promoted the stabilization of T-ZrO 2 , smaller grain sizes, increased specific surface area, and strong acidity, which in turn positively affected the catalytic performance. In addition, a possible reaction mechanism of Fe-promoted SO 4 2-/ZrO 2 catalyst for catalyzing the alkylation of DPA with NON was proposed. [Display omitted] • Fe-promoted SO 4 2-/ZrO 2 was developed and applied firstly to synthesize nonylated diphenylamine by alkylation of DPA and NON. • The NFe 2.50 S 1.0 Z performed excellent reactivity and regenerability with high yields of mono- and di-nonyl-diphenylamine. • Fe promoting effects on structural and acid sites of the catalyst were thoroughly elucidated. • The mechanistic reaction pathway was proposed for the alkylation of DPA with NON over Fe-promoted SO 4 2-/ZrO 2 catalyst. [ABSTRACT FROM AUTHOR]

The synthesis of cyclopropanes by the cyclization of allylic diazoesters is well-known. In prior studies toward the sesquiterpenoid euonyminol, we attempted to carry out an intramolecular cyclopropanation of an allylic diazoester containing an electronically-unbiased alkene embedded in a 6-oxa-bicyclo[3.2.1]-oct-3-ene skeleton. We obtained exclusively a product arising from 1,2-addition of oxygen and carbon (oxyalkylation) to the alkene. While oxyalkylation products have been reported when electron-rich alkenes (e.g. enol ethers) are employed, oxyalkylation products derived from electronically-unbiased alkenes are rare. Here, we establish that the oxyalkylation is general for a range of 6-oxa-bicyclo[3.2.1]-oct-3-ene substrates and show that these products form competitively in the cyclization of simpler α-diazo-β-ketoesters. Our data suggest increasing charge separation in the transition state for the addition promotes the oxyalkylation pathway. [Display omitted] [ABSTRACT FROM AUTHOR]

The synthesis of value-added aromatic products, such as para-ethyl-toluene (PetT), from the greenhouse gas carbon dioxide (CO 2) and renewable hydrogen (H 2) is greatly desired. However, considerable challenges arise due to complex kinetics and difficulties in arranging multiple active components. Herein, we present a strategy for the selective synthesis of PetT via CO 2 hydrogenation in the presence of ethylbenzene via tandem reactions over a composite catalyst comprising Zn-Zr binary oxide and a modified crystal-stacking HZSM-5 zeolite, achieving over 70% PetT selectivity in the ethyl-toluene (ET) isomers (∼80% in the C 5+ hydrocarbons). State-of-the-art (quasi) in situ characterizations and corresponding theoretical calculations confirmed the designed reaction route involving stepwise activation of CO 2 to methoxy species and enhanced aromatic cycles for the formation of C–C bonds. And precisely controlled transfer and transformation of intermediate methoxy species contribute to the promoted performance in the selective synthesis of PetT. [Display omitted] • 80% ET containing 70% PetT was obtained over an oxide-zeolite composite catalyst. • Stepwise CO 2 activation and enhanced aromatic cycle afforded the tandem reactions. • Methoxy transferring makes great effect on the efficiency of tandem processes. • Key role of surface methoxy species is unveiled by experimental and DFT results. • Increasing components intimacy and zeolite acidity help increase performance. [ABSTRACT FROM AUTHOR]

Bromophenols (BPs) are a class of ubiquitous emerging halogenated pollutants. Their 19 congeners are problematically separated and detected. This work described the separation and detection of 19 BP congeners by gas chromatography-mass spectrometry (GC-MS). Investigations into the derivatization of bromophenols were carried out using two silylation reagents (N,O-bis(trimethylsilyl)trifluoroacetamide and N-methyl-N-(trimethylsily)trifluoroacetamide), two alkylation reagents (methyl iodide and trimethylsilyldiazomethane) and acetic anhydride prior to GC-MS analysis. Optimal chromatographic separation, sensitivity, and linearity were achieved after BP derivatization using acetic anhydride, featuring the equipment detection limits of 0.39–1.26 pg and correlation coefficients of 0.9948–0.9999 (linear range: 0.5–250 ng mL−1) for all 19 BP congeners. Furthermore, the simultaneous determination of 19 bromophenols and 19 bromoanisoles, common environmental transformation products of BPs, is also demonstrated. The improved analytical performance on GC-MS after derivatization would benefit investigations on the environmental origins, behaviors and fates of BPs and their environmental metabolites. [Display omitted] • Five derivatization reagents were compared for bromophenol analysis. • Acetylation achieved the best selectivity, linearity, and sensitivity. • All bromophenols and bromanisoles can be resolved on GC-MS using acetylation. [ABSTRACT FROM AUTHOR]

[Display omitted] Methyl 4-trifluoro-2-isopropyl-4-oxobutanoate prepared by the improved procedure was cyclized with hydrazines to afford the title pyrazole derivatives. N - and O -alkylation of 4-isopropyl-1-phenyl-3-(trifluoromethyl)pyrazol-5-ol gave trifluoromethyl analogues of Propyphenazone and 5-alkoxy derivatives. 4-Isopropylpyrazoles containing O -butoxy moiety with a terminal trifluoromethyl or acyloxy group were found to demonstrate a promising analgesic activity. [ABSTRACT FROM AUTHOR]

The application of industrial kraft lignin is limited by its low molecular weight, dark color, and low solubility. In this work, an efficient crosslinking reaction with N,N-Dimethylformamide (DMF) and 1,6-dibromohexane was proposed for adjusting the molecular weight and color of lignin. The chemical structure of alkylation lignin was systematically investigated by gel permeation chromatography (GPC), ultraviolet spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and 2D heteronuclear single quantum correlation nuclear magnetic resonance (HSQC NMR) spectra. After the alkylation modification, the molecular weights of the lignin were increased to 1643%. The resinol (β-β), β-aryl ether (β-O-4), and phenylcoumaran (β-5) linkages were still the main types of the linkages. The formation of β-β linkage would be inhibited at high temperatures. The color reduction of lignin can be attributed to the low content of chromophores and low packing density. This alkylation lignin will be a new and general approach for developing molecular weight-controlled and light-colored lignins, which can find more applications in cosmetics, packing, and other fields. [ABSTRACT FROM AUTHOR]