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We propose an efficient algorithm for a minimum free energy path calculation based on the path integral hybrid Monte Carlo (PIHMC) method by combining the climbing image-nudged elastic band (CI-NEB) and the thermodynamic integration (TI) methods. Here, the CI-NEB and the TI methods are used to find a transition state along the reaction path and evaluate the free energy path, respectively. Our algorithm is applied to the Walden inversion reaction of the hydronium ions (H3O+). The numerical results show that the computational effort by our algorithm is significantly reduced compared to that of the previously proposed algorithm combining PIHMC without losing accuracy. We also demonstrate the importance of temperature and isotope effects on the addition reaction of hydrogen isocyanide to formaldehyde. In this reaction, the nuclear quantum effect causes the structural change at the TS and decreases the energy barrier. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) and NO–water clusters play crucial roles in the D-region of the atmosphere because it is postulated that NO+ reacts with H2O to produce nitrous acid (HONO) and H3O+. HONO is the major precursor of the hydroxyl radicals leading to the formation of secondary pollutants. The sources of atmospheric HONO, however, are not fully understood. Previously, the sequential H2O addition reaction, H2O + NO+(H2O)n, and the bi-molecular collision reaction, NO+ + (H2O)n, have been investigated by both experiments and theoretical calculations to determine the formation mechanism of HONO. However, the photo-reactions from NO(H2O)n neutral clusters were not considered for the formation mechanism of HONO. In this study, the intra-cluster reactions of NO+(H2O)n clusters, following ionization of the parent neutral cluster of NO(H2O)n, were investigated using the direct ab initio molecular dynamics method. When n = 4, [NO+(H2O)4]ver [vertical ionization state of NO(H2O)n] yielded HONO and hydrated H3O+ after the intra-cluster reaction, and the reaction time was calculated to be 150 fs. The reaction is expressed as [NO+(H2O)n]ver → HONO + H3O+(H2O)n−2 (reactive) (n > 3). Larger clusters of [NO+(H2O)n]ver (n = 5–8) also yield HONO. In contrast, in smaller clusters (n = 1–3), only solvent re-orientation around NO+ occurred after the ionization: [NO+(H2O)n]ver → NO+(H2O)n (solvent re-orientation) (n = 1–3). The hydration energy of H3O+, which depends on the cluster size (n), plays an important role in promoting the formation of HONO. The reaction mechanism is discussed based on theoretical results. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) and NO–water clusters play crucial roles in the D-region of the atmosphere because it is postulated that NO+ reacts with H2O to produce nitrous acid (HONO) and H3O+. HONO is the major precursor of the hydroxyl radicals leading to the formation of secondary pollutants. The sources of atmospheric HONO, however, are not fully understood. Previously, the sequential H2O addition reaction, H2O + NO+(H2O)n, and the bi-molecular collision reaction, NO+ + (H2O)n, have been investigated by both experiments and theoretical calculations to determine the formation mechanism of HONO. However, the photo-reactions from NO(H2O)n neutral clusters were not considered for the formation mechanism of HONO. In this study, the intra-cluster reactions of NO+(H2O)n clusters, following ionization of the parent neutral cluster of NO(H2O)n, were investigated using the direct ab initio molecular dynamics method. When n = 4, [NO+(H2O)4]ver [vertical ionization state of NO(H2O)n] yielded HONO and hydrated H3O+ after the intra-cluster reaction, and the reaction time was calculated to be 150 fs. The reaction is expressed as [NO+(H2O)n]ver → HONO + H3O+(H2O)n−2 (reactive) (n > 3). Larger clusters of [NO+(H2O)n]ver (n = 5–8) also yield HONO. In contrast, in smaller clusters (n = 1–3), only solvent re-orientation around NO+ occurred after the ionization: [NO+(H2O)n]ver → NO+(H2O)n (solvent re-orientation) (n = 1–3). The hydration energy of H3O+, which depends on the cluster size (n), plays an important role in promoting the formation of HONO. The reaction mechanism is discussed based on theoretical results. [ABSTRACT FROM AUTHOR]

Phenylacetylene plays a critical role as an intermediate in PAH formation in hydrocarbon flames. In this work, the autoignition characteristics of phenylacetylene were investigated behind reflected shock waves. Ignition delay times were measured at temperatures ranging from 1228 to 1813 K, pressures of 2, 4, and 10 atm, equivalence ratios of 0.5, 1.0, and 2.0, as well as fuel mole fractions of 0.1% and 0.2%. The effects of temperature, pressure, equivalence ratio, and mole fractions on ignition delay time were investigated, and quantitative relationships were obtained by regression analysis of the experimental data. A detailed oxidation mechanism of phenylacetylene based on NUIGMech1.1 was proposed and verified using ignition data. Reaction pathway and sensitivity analyses have been carried out to investigate the significant reaction pathways in the ignition process and key reactions that affect the ignition delay time. The addition reactions by O and OH species contribute significantly to phenylacetylene consumption and promote fuel ignition. Finally, a comparison of the ignition delay times of ethylbenzene, styrene, and phenylacetylene was conducted in this study, and kinetic analyses have been conducted to investigate the impact of different side chains attached to aromatic rings on the ignition of these C8 aromatics. [ABSTRACT FROM AUTHOR]

Prins reaction of isoprenol with butanal provides important intermediate 4-methyl-2-propyltetrahydro-2H-pyran-4-ol, which can be esterified to 4-methyl-2-propyltetrahydro-2H-pyran-4-yl acetate. This desired fragrance with fruity and rose scent is known, e.g., as Clarycet®. Molybdenum-modified MCM-41 materials were obtained by a wet impregnation method using a water solution of ammonium molybdate. We prepared several materials with different MoO3 loadings. These materials were thoroughly characterized (nitrogen physisorption, acidity—temperature-programmed desorption, elemental composition, etc.). The activity of prepared materials was tested in Prins reaction of isoprenol with butanal in batch arrangement. The influence of various reaction conditions (catalyst type, solvent, and water addition) was tested. We showed that modification of MCM-41 with MoO3 led to a significant increase of catalytic activity (butanal conversion at 4 h of reaction: 7% for nonmodified MCM-41 compared to 93% for material 5 wt% of MoO3-MCM-41). Water addition to the reaction mixture positively influenced the selectivity of the desired substituted tetrahydropyranol (selectivity > 70%). Mo-modified materials were also active in the esterification of 4-methyl-2-propyltetrahydro-2H-pyran-4-ol with acetanhydride to 4-methyl-2-propyltetrahydro-2H-pyran-4-yl acetate providing desired product after 5 h with 100% selectivity and total conversion. Reaction in the "one-pot" arrangement was also performed. [ABSTRACT FROM AUTHOR]

Methotrexate (MTX) is a chemotherapy agent and immune system suppressant that is widely used to treat a variety of malignant and nonmalignant diseases. Due to some drawbacks of the existing methods for the determination of MTX in aquatic and real samples, we prepared a new, simple, and selective dual‐mode fluorometric and electrochemical approach based on peroxidase‐mimic [Mo36] polyoxomolybdate nanoclusters (POMo) for sensing MTX. A turn‐on–off fluorometric approach for the detection of MTX was developed, which was based on the inhibition of the emission intensity of the terephthalic acid (TA)‐H2O2 system upon the addition of MTX to the reaction solution. The electrocatalytic performance of the obtained POMo was studied after making a carbon paste electrode (CPE) utilizing cyclic voltammetry and amperometry analysis. Under the optimum condition, good linearity was observed between the quenched emission intensity of the system and MTX dosage in the range of 0.5–250 μM with a limit of detection (LOD) of 0.91 μM. The electrochemical method illustrated a much better response with an extensive linear range of 0.01–475 μM and a lower LOD (1.61 nM). Analytical recoveries and RSD% values were, respectively, in the range of 87.72%–110% and 0.33%–1.32% for the fluorometric system and 96%–106% and 0.77%–1.02% for the electrochemical platform. Finally, the selectivity of the sensor was evaluated against various common interfering species, and the results indicated satisfactory selectivity of the POMo dual‐mode system towards MTX. [ABSTRACT FROM AUTHOR]

Applications of macrocyclic compounds and their various metal complexes in biological fields have notably increased. Therefore, it is reasonable to synthesize novel macrocyclic compounds and assess their biological properties. In this research, several new Ni(II) complexes were prepared using hexamethyltetraaza macrocycles, and their biological activity was studied. Specifically, a fourteen-membered tetraaza macrocyclic diene ligand in its dihydroperchlorate form, Me6[14]diene⋅2HClO4 (L⋅2HClO4), along with its isomers tet-a and tet-b in their saturated 'ane' forms, were employed for complexation with Ni(II) acetate, followed by the addition of NaClO4. The process resulted in the formation of square planar [Ni[(L´)](ClO4)2 (L´ = L, tet-a, or tet-b) and octahedral [Ni(tet-b)(ClO4)2] complexes. Furthermore, axial addition reactions involving SCN–, Cl–, Br–, and I– with [Ni[(L´)](ClO4)2 led to the formation of six-coordinated octahedral complexes, including [Ni(L)(NCS)2], [Ni(tet-a)(NCS)2], [Ni(tet-b)(NCS)2] [Ni(tet-b)Cl2], [Ni(L)Br2], [Ni(tet-b)Br2] and [Ni(tet-b)I2]. Additionally, axial substitution reaction on the complex [Ni(tet-b)(ClO4)2] with SCN– produced a five-coordinated square pyramidal complex, [Ni(tet-b)(NCS)](ClO4). Modern analytical and spectroscopic techniques were used to characterize these complexes. It was observed that these complexes exhibited different geometries and electrolytic properties in different organic solvents where the Ni(II) showed different coordination modes. These complexes also displayed moderate antimicrobial activity against various bacteria. [ABSTRACT FROM AUTHOR]

The C–F bond activation of perfluoronaphthalene by 5-SIDipp led to the formation of dicationic salts with two fluorides (3·2HF2) or heptafluorodiborate (3·2B2F7) as counter-anions. The anion exchange reaction of 3·2B2F7 with NBu4PF6 afforded a highly luminescent 3·2PF6. The in situ addition of cobaltocene in the reaction mixture of 5-SIDipp and perfluoronaphthalene led to a distinct Co(I) species. [ABSTRACT FROM AUTHOR]

Overcoming the significant volume strain in silicon‐based anodes has been the focus of research for decades. The strain/stress in silicon‐based anodes is inversely proportional to their size. In this study, we design atomic Si sites to achieve the ultimate size effect, which indeed exhibits a zero‐strain feature. Compared with conventional silicon‐based anodes with alloying addition reactions, the lithium‐ion storage mechanism of atomic Si sites is solid‐solution reactions, which brings about the zero‐strain feature. Additionally, the ligand structure of atomic Si sites remains constant during cycling. This zero‐strain feature results in excellent cycling stability. Furthermore, the exposed atomic Si sites enhance the electrochemical reaction kinetics, leading to outstanding rate performance. Moreover, the anode inherits the advantages of silicon‐based anodes, including a low working voltage (~0.21 V) and high specific capacity (~2300 mAh g−1 or ~1203 mAh cm−3). This work establishes a novel pathway for designing low/zero‐strain anodes. [ABSTRACT FROM AUTHOR]

Individuals suffering from voice disabilities have limited access to currently available automation technologies that operate through voice commands. To address this issue, an alternative voice recognition approach is essential without directly monitoring the audio signals generated from the vocal cord. In this work, the design of a chemically reactive and conductive sponge is reported to create an underwater vibration sensor with a fast response time and high sensitivity, through orthogonal modulation of conductivity (40–2150 kΩ), water repellence (0°–154°) and mechanical properties (0.32–2.63 MPa). This class of porous sponge sensors enables the identification of subtle water waves generated at the air–water interface and extends its utility to detecting a variety of locomotion (squatting, jumping, walking, etc.), as well as automated voice recognition using a deep learning model without direct contact with the human body. Overall, this underwater vibration sensor provides a novel basis for remote interaction with automated technologies, which finds use in medical diagnostics, human‐machine interfaces, and underwater communication systems. [ABSTRACT FROM AUTHOR]

Aiming at the problem of excessive swelling of conventional microspheres for oilfield use, a novel amphiphilic polymerizable crosslinker (AE) was synthesized by quaternary ammonium modification of an unstable crosslinker (AE) using acrylamide, 2-acrylamido-2-methylpropanesulfonic acid as the monomers, N,N′-methylene bisacrylamide as the stabilizing crosslinker, ammonium peroxysulfate and sodium bisulfite as the initiator, and water as the solvent by using a reversed microemulsion method. Double-networked nanomicrospheres were prepared. The preparation conditions of the microspheres were optimized by the surface response method, focusing on the effects of the initiator addition and reaction temperature, and total crosslinker addition on the formation of nanomicrospheres. The samples were characterized by FTIR, TGA, laser particle sizer, and SEM to evaluate the retarded expansion performance and the modulation drive performance. The results showed that the optimal conditions for the preparation of microspheres were m(oil phase):m(water phase) = 3:2, stirring speed of 550 r/min, total crosslinking agent dosage of 0.6% (based on the total mass of monomers, hereinafter the same), initiator dosage of 0.30%, reaction temperature of 45 °C, and reaction time of 4 h. Compared with the conventional polymer microsphere PAM, PAE was slow-expanded for 45 d at 60 °C, and the expansion multiplier was about 16 times, with slow-expansion characteristics; the blocking rate of PAE reached 98.3%, the oil repulsion rate was 73.11%, and the increase in the recovery rate could be up to 11.23%. In this paper, a new type of nanomicrosphere material is investigated to realize the efficient implementation of oil field conditioning and driving. [ABSTRACT FROM AUTHOR]

The first stereodivergent umpolung 1,5-conjugate addition reaction via synergistic Pd/Cu catalysts is reported. By dictating the absolute configuration of each chiral ligand ligated to corresponding metals, all four stereoisomers of the products are easily achieved. A series of amino acid moieties are introduced to the γ-position of the conjugated esters in high yields with excellent diastereoselectivities and enantioselectivities. The downstream transformations highlight the synthetic value of the method. [ABSTRACT FROM AUTHOR]

A flexible, shape-editable transparent wood (ATW) composite containing acetal linkages was prepared simultaneously through free radical polymerization and addition reaction between vinyl ether bonds and hydroxyl groups. In this system, the anisotropic hierarchical structure of wood acted as a reinforced skeleton, the flexible chain segment ensured flexibility at room temperature, and the dynamic acetal bonds were responsible for the shape memory and editability under relatively mild conditions, verifying the expanding applications of functionalized wood-based materials. [ABSTRACT FROM AUTHOR]

The anionic polyaddition of methyl‐substituted 1,1‐diphenylethylene derivatives, catalyzed by lithium diisopropylamide, was examined. Polymerization of the monomer was conducted at 50°C in THF with the addition of diisopropylamine. NMR and MALDI‐TOF‐MS analyses of the obtained polymer indicate that polymerization proceeded via a polyaddition reaction, in other words, repetition of the lithium amide‐induced metalation reaction of the monomer at the methyl group and the subsequent nucleophilic addition reaction of the corresponding benzyllithium with the vinyl group in the monomer. On the other hand, the unsubstituted diphenylethylene monomer could not be polymerized by the same reaction condition. Consequently, the resulting polymer was indeed obtained by an anionic polyaddition mechanism. In conclusion, a novel hydrocarbon polymer containing a phenyl group in the main chain of the repeating unit was successfully obtained from a methyl‐substituted 1,1‐diphenylethylene monomer. [ABSTRACT FROM AUTHOR]

The present study describes the synthesis of various bioactive compounds, including bis‐coumarins, bis‐lawsones, bis‐dimedones, and bis‐indolylmethanes, using a novel catalytic system called "Brønsted acid saponin combined catalyst" (BASapC). The BASapC was formed by combining p‐toluenesulfonic acid (PTSA) and saponin in an aqueous medium. The prepared BASapC proved to be effective in facilitating cascade‐type Knoevenagel–Michael addition reactions between various aromatic aldehydes with 4‐hydroxycoumarin, lawsone, dimedone, or indole at 80 °C. In the BASapC system, PTSA acted as a powerful Brønsted acid, activating reactants, whereas saponin served as a natural surfactant, enhancing the solubility of organic compounds in water. This catalytic approach established a straightforwardness and robustness of diversity‐oriented synthesis (DoS), delivering the desired products with good to excellent yields. Additionally, the BASapC exhibited recyclability for at least four cycles without significant loss of activity. [ABSTRACT FROM AUTHOR]

Since the review of Yorimitsu and Oshima in 2010, the past 15 years have witnessed significant progresses in the application of 1‐alkynylphosphorus compounds in organic synthesis. Owing to the reactive carbon‐carbon triple bond in association with the electron‐withdrawing phosphoryl group, they easily undergo transition metal‐catalyzed nucleophilic addition reactions at the β‐position with carbon‐ and heteroatom‐based nucleophiles to afford structurally diverse 1‐alkenyl phosphorus compounds. Especially, when 1‐alkynylphosphonates or phosphinates are used, intramolecular substitution reactions on P‐atom might occur in some cases, which would result in the formation of P‐based heterocycles. In addition, the existing triple bond makes them prone to go through addition reaction initiated cyclization reactions and [2+2], [2+3], [2+4], [2+5] and [2+2+2] cycloaddition reactions with other unsaturated bonds, which provides an efficient access to various P‐based heterocycles and phosphorylated carbon‐ and heterocycles. [ABSTRACT FROM AUTHOR]

Optically active molecule architectures stand as an important class of organic compounds and occupy a key role in academic and industrial communities. Particularly, the molecules bearing quaternary carbon are of vital importance because of its favorable conformation and valuable three‐dimensional molecules, which frequently play a key role in a broad spectrum of functional materials, pharmaceutical relevant natural molecules, and agrochemicals. Over the past few decades, a large number of synthetic strategies for the enantioselective construction of compounds with chiral quaternary carbon centers have been the focus of a number of research initiatives. In this review, the state‐of‐the‐art toward the synthesis of enantioenriched molecules bearing quaternary stereocenters are summarized, which could be segmented into four categories: 1) Construction of optically active quaternary carbon centers by addition to prochiral sp2 carbon; 2) Construction of optically active all‐carbon quaternary stereocenters via substitution at non‐chiral tetra‐substituted carbon; 3) Construction of optically active all‐carbon quaternary stereocenters via kinetic resolution; 4) Construction of optically active all‐carbon quaternary stereocenters via desymmetrization reactions. [ABSTRACT FROM AUTHOR]

Different spectroscopic techniques and Density Functional Theory (DFT)/Time-Dependent Density Functional Theory (TDDFT) calculations have been employed to investigate the dual channel CN− detection behaviour of the developed chemo-dosimeter (AK3). The CN− with AK3 reaction triggered a colour change from pale yellow to colourless and enhanced fluorescence. UV–Vis, fluorescence, 1H & 13C NMR and mass techniques coupled with theoretical calculations (Mulliken charges, dihedral angles) revealed that the CN− sensing process mechanism involves deprotonation of the N–H group followed by nucleophilic addition reaction. Detailed TD-DFT calculations showed that the relaxation of excited electrons from LUMO and to two different ground states is responsible for the weak/moderate fluorescence of AK3. Nucleophilic addition of CN− to the C-atom of the CH = CH bridge terminated the π-conjugation between donor and acceptor regions, reduced the coplanarity, decreased the ICT transition and consequently enhanced the fluorescence of the probe. The practical utility of the probe was demonstrated by detecting cyanide in food materials and determining CN− in environmental water samples. [ABSTRACT FROM AUTHOR]

As a significant variant of the Michael reaction, the 1,6‐addition reaction has undergone considerable development over the past decade. This effective strategy enables the synthesis of a variety of novel and potentially bioactive functional molecules. In this review, we summarize the recent progress in NHC‐catalyzed 1,6‐addition reactions, highlighting their efficiency in the rapid synthesis of complex functional molecules. We also provide our perspectives on the future development of this dynamic and highly active research area. [ABSTRACT FROM AUTHOR]

A thorough understanding of the lignin–carbohydrate complex (LCC) structure has a significant meaning in the high-value utilization of lignocellulose. In this work, the complex (DHPKGC) was obtained by an addition reaction between konjac glucomannan (KGM) and quinone methides generated in the synthesis of dehydrogenation polymers (DHPs) to simulate the formation of LCCs. The effect of pH on the prepared DHPKGC was investigated. The structure of the DHPKGC was characterized by Fourier Transform Infrared (FTIR), 13C-Nuclear Magnetic Resonance (13C-NMR), and two-dimensional Heteronuclear Single Quantum Coherence Nuclear Magnetic Resonance (2D HSQC NMR) analyses. The results indicated the pH of 4.0 was conducive to the polymerization reaction between DHPs and oxidized KGM by the TEMPO/NaClO/NaBr system. In addition, the resultant DHPKGC was connected by benzyl ester linkages. Overall, this study aims to gain greater insight into the process of LCC formation in plants. [ABSTRACT FROM AUTHOR]

(E)-6-Methoxy-1-methyl-3-(2-(3-methyl-4-nitroisoxazol-5-yl)vinyl)quinolin-2(1H)-one dye (MQI) has been synthesized, and its structural and electronic properties have been characterized by employing UV-vis spectroscopy in combination with computational methods. The MQI dye has been assessed as an activated Michael acceptor-type probe toward bisulfite ions. This reaction was kinetically tested in different mild, cationic (cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, and cetylpyridinium bromide), and zwitterionic (N-decyl-N,N-dimethyl-3-ammonio-1-propanesulfonate, N-tetradecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate, and N-hexacyl-N,N-dimethyl-3-ammonio-1-propanesulfonate) micellar solutions at pH ∼ 5.5. Both micellar media remarkably allow the addition reactions, increasing the reactivity of MQI towards bisulfite ions, the biggest effects were found in the presence of cationic micelles. The binding constants of MQI with the micelles and the rate constants were determined from kinetic data, which were interpreted on the basis of the pseudophase kinetic model. The kinetic study and the product analysis allow us to highlight the relevant role of the association between MQI dye and the micellized surfactant, allowing efficient nucleophilic addition of bisulfite ions. The findings of this work will be valuable for the use of micellar solutions as an alternative medium to replace the use of toxic solvents to carry out organic reactions to perform nucleophilic addition reactions of bisulfite. [ABSTRACT FROM AUTHOR]

An atom‐economical sequential‐flow synthesis of donepezil, a widely prescribed drug for Alzheimer's disease, was accomplished using inexpensive, commercially available precursors. This achievement was made possible by reconfiguring the synthetic route to include only heterogeneous catalytic addition and condensation reactions, with a particular emphasis on skeletal transformation and bond formation through hydrogenation processes. Notably, water was the sole byproduct in this synthesis. A crucial aspect of this work was the development of appropriate continuous‐flow processes to achieve a one‐flow synthesis. This was accomplished by implementing in‐line treatments of the main reaction stream to eliminate inhibitory factors that could affect catalyst performance in the hydrogenation steps. [ABSTRACT FROM AUTHOR]

The reaction of unsubstituted α-nitrocinnamic nitrile with 1-methylpyrrole ends with the formation of an AdN product, whereas the reactions of 2-aryl-2-nitroacrylonitriles with such N,N- and N,S-binucleophiles as hydrazine, phenylhydrazine, and o-aminothiophenol lead to transformation products of the initially formed adducts, linear azines and phenylhydrazones, or to a heterocyclic benzothiazole structure. [ABSTRACT FROM AUTHOR]

Synthesis of functionalized 1,3‐indandiones containing‐cyclopentenones and ‐benzotropones has been achieved by the reaction of 1,5‐diphenylpenta‐1,4‐diyn‐3‐ones with 1,3‐indandiones, bindone respectively. The developed method involves Michael‐anti‐Michael addition cascade reactions under transition‐metal‐free conditions. This is the first report to synthesise diverse benzotropone fused with 1,3‐indandiones under transition metal‐free conditions from bindone. [ABSTRACT FROM AUTHOR]

Developing effective latent curing agent for rapid curing of epoxy resins at low temperatures remains challenging. This study reports a latent curing agent, ortho‐cresol phenolic epoxy resin‐bisphenol A (EOCN‐BPA), prepared through the addition reaction of o‐methyl phenolic epoxy resin with BPA. When blended with dicyandiamide (DICY) in a 1:3 molar ratio, EOCN‐BPA/DICY is used to cure a linear epoxy phenolic novolac (EPN) resin (epoxy equivalent: 550 g eq−1, softening point: approximately 82°C), at an onset curing temperature of 90°C, which is considerably lower than the onset curing temperature of DICY with EPN (160°C). However, EOCN‐BPA does not react with EPN without a catalyst. Therefore, this latent curing system is successfully applied in powder coatings, rapid curing at 120°C within 3 min without an additional catalyst, outperforming the EPN/EOCN‐BPA system using cocatalyst 2‐methylimidazole. Consequently, DICY catalyzes the curing reaction between the phenol hydroxyl group and epoxy resin and participates in it. The prepared powder coating exhibits excellent storage stability, maintaining its properties for over 3 months at room temperature. These findings demonstrate the excellent latent properties of EOCN‐BPA/DICY, highlighting its potential as a highly effective latent curing agent. [ABSTRACT FROM AUTHOR]

Chiral tertiary alcohols are an important structural motif, however, the general and efficient methodologies for their synthesis are less reported. Herein, we report a Ni(ІІ)-catalyzed asymmetric alkenylation and arylation of aryl ketones with organoborons under air via a 1,5-metalate shift strategy to obtain chiral tertiary allylic alcohols and diaryl alcohols. The reaction demonstrates good functional group tolerance and delivers chiral tertiary alcohols with good to excellent results. Furthermore, this method can be applied to the late-stage modification of drugs and the efficient synthesis of natural products. Notably, the reaction proceeds through an outer-sphere mechanism. The Ni(II) complex functions both as a Lewis acid to activate the ketone and create a chiral environment, and as coordination bridge linking the ketone and the organoboron-derived "ate" complex, facilitating the 1,5-metalate shift without forming a C-Ni bond. This approach contrasts with traditional transition metal-catalyzed nucleophilic addition reactions that involve carbon-metal bond formation. Chiral tertiary alcohols are an important structural motif, but the general methodologies for the synthesis are less reported. Herein, the authors report a Ni(ІІ)-catalyzed asymmetric alkenylation and arylation of aryl ketones with organoborons under air via a 1,5-metalate shift to obtain chiral tertiary allylic alcohols and diaryl alcohols. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculation has been used to reveal palladium‐catalyzed mode of diaziridinone ring activation. Our theoretical studies found that oxidative addition of di‐tert‐butyldiaziridinone to Pd(II) can give a high valent Pd(IV) intermediate, along with the cleavage of N─N bond in di‐tert‐butyldiaziridinone through a concerted three‐membered‐cyclic transition state. Subsequent transformations via reductive elimination and β‐N elimination give the desired indolo[3,2‐b]indole product. The competitive activation modes such as metathesis and migratory insertion can be excluded in our selected model reaction. The rate‐determining step of this reaction is the oxidative addition of di‐tert‐butyldiaziridinone step. Distortion‐interaction analysis was conducted to reveal that the oxidative addition mode of di‐tert‐butyldiaziridinone is superior to the metathesis mode due to the lower interaction energy. [ABSTRACT FROM AUTHOR]

This study introduces a novel photoelectrochemical (PEC) sensor for the highly selective detection of sulfur dioxide (SO2) using an organic photoactive molecule probe (OPM). OPM is synthesized through a one‐step coupling reaction, featuring a typical photosensitizer D‐π‐A structure. By covalently bonding OPM with a TiO2 substrate, a PEC sensor is constructed, exhibiting a significant photocurrent response under visible light excitation. The specific addition reaction between SO2 and OPM disrupts its conjugated structure, reducing the photocurrent response and achieving highly selective detection of SO2. The sensor demonstrates excellent performance in real water samples, emphasizing its practical applications. [ABSTRACT FROM AUTHOR]

Objective: The study commenced with the conversion of 4-(1H-indol-3-yl)butanoic acid (I) into ethyl 4-(1H-indol-3-yl)butanoate (II), succeeded by the synthesis of the hydrazide nucleophile, 4-(1H-indol-3-yl)butanohydrazide (III). Methods: Following this, nucleophilic addition reactions of (III) with various electrophilic aldehydes (IVa–IVg) were conducted to yield the targeted derivatives (Va–Vg/Vʹa–Vʹg). The structural elucidation of all synthesized compounds relied on IR, 1H, 13C NMR, HMBC, and CHN analysis. Results and Discussion: Evaluation of the inhibitory effects of these heterocyclic butanohydrazides (Va–Vg/Vʹa–Vʹg) against the α-glucosidase enzyme revealed significant inhibition by compounds (Vg/Vʹg) compared to the standard. Conclusions: Hemolytic analysis indicated mild cytotoxicity towards red blood cell membranes, indicating the potential of these molecules as nontoxic medicinal scaffolds for skin pigmentation and related disorders. [ABSTRACT FROM AUTHOR]

This review introduces the synthetic organic chemical value of α‐bromocarbonyl compounds with tertiary carbons. This α‐bromocarbonyl compound with a tertiary carbon has been used primarily only as a radical initiator in atom transfer radical polymerization (ATRP) reactions. However, with the recent development of photo‐radical reactions (around 2010), research on the use of α‐bromocarbonyl compounds as tertiary alkyl radical precursors became popular (around 2012). As more examples were reported, α‐bromocarbonyl compounds were studied not only as radicals but also for their applications in organometallic and ionic reactions. That is, α‐bromocarbonyl compounds act as nucleophiles as well as electrophiles. The carbonyl group of α‐bromocarbonyl compounds is also attractive because it allows the skeleton to be converted after the reaction, and it is being applied to total synthesis. In our survey until 2022, α‐bromocarbonyl compounds can be used to perform a full range of reactions necessary for organic synthesis, including multi‐component reactions, cross‐coupling, substitution, cyclization, rearrangement, stereospecific reactions, asymmetric reactions. α‐Bromocarbonyl compounds have created a new trend in tertiary alkylation, which until then had limited reaction patterns in organic synthesis. This review focuses on how α‐bromocarbonyl compounds can be used in synthetic organic chemistry. [ABSTRACT FROM AUTHOR]

Covalent adaptive networks (CANs) are capable of undergoing segment rearrangement after being heated, which endows the materials with excellent self-healing and reprocessing performance, providing an efficient solution to the environment pollution caused by the plastic wastes. The main challenge remains in developing CANs with both excellent reprocessing performance and creep-resistance property. In this study, a series of CANs containing dynamic covalent benzopyrazole-urea bonds were developed based on the addition reaction between benzopyrazole and isocyanate groups. DFT calculation confirmed that relatively low dissociation energy is obtained through undergoing a five-member ring transition state, confirming excellent dynamic property of the benzopyrazole-urea bonds. As verified by the FTIR results, this nice dynamic property can be well maintained after incorporating the benzopyrazole-urea bonds into polymer networks. Excellent self-healing and reprocessing performance is observed by the 3-ABP/PDMS elastomers owing to the dynamic benzopyrazole-urea bonds. Phase separation induced by the aggregation of the hard segments locked the benzopyrazole-urea bonds, which also makes the elastomers display excellent creep-resistance performance. This hard phase locking strategy provides an efficient approach to design CANs materials with both excellent reprocessing and creep-resistance performance. [ABSTRACT FROM AUTHOR]

Quinolines are very important materials in organic synthesis due to their wide range of biological activities as well as representing one of the most research area in medicinal chemistry. Quinolines have many applications in design and synthesis of multiple heterocyclic compounds with a wide variety of biological significance. Quinolines fused heterocycles at face b using different synthetic methodologies as well as variable precursors and reaction conditions were the aim of the current review. [ABSTRACT FROM AUTHOR]

Traditional polyamide elastomer synthesis via polycondensation of diamines and dicarboxylic acids involves high energy use and by‐product mass loss. Here, we present a novel method using thiol‐Michael addition click chemistry to produce these elastomers under mild conditions, marking the first use of this strategy. The polymerization involves coupling bis‐acrylamide (BAA) with 3,6‐dioxa‐1,8‐octanedithiol (DODT), catalyzed by 1,5‐diazabicyclo[4.3.0]non‐5‐ene (DBN). BAA is synthesized from polyetheramine and acryloyl chloride, creating a compound with amide groups and carbon double bonds at chain ends. These double bonds' electron‐withdrawing effect facilitates the click reaction efficiently, avoiding high energy and mass loss. The resulting polymers have a molecular weight of approximately 10,000 g/mol, verified by 1H NMR and FTIR spectroscopy, which show amide group presence. SAXS and AFM confirm nanophase separation of these groups. Tensile strength ranges from 0.235 to 0.542 MPa, decreasing with lower polyetheramine content but still showing notable elasticity. This method's low energy use, no mass loss, and good mechanical properties make it promising for developing high‐performance polyamide plastics and elastomers, appealing to researchers in both academia and industry. Highlights: High elasticity, softness, and high tensile polyamide elastomer.Thiol‐Michael addition click reaction conforms to atomic economy.Long molecular chain contains extraordinary evolution of hydrogen bonding. [ABSTRACT FROM AUTHOR]

Herein, we report a controllable and versatile strategy for the synthesis of highly dispersed Co nanoparticles embedded in open‐channel hierarchically porous N/O‐doped carbon skeleton. Moreover, the pore sizes of the hierarchical structures can be easily tuned by adjusting the size of precursors. The as‐obtained Co@NC‐2ST exhibits unprecedented activity and selectivity in the oxidative esterification of 5‐hydroxymethylfurfural (HMF) to dimethyl furan‐2,5‐dicarboxylate under base‐free and atmospheric conditions. In particular, the achieved turnover frequency value is an order of magnitude higher than that of the state‐of‐art heterogeneous catalysts reported to date. A combination of experimental and density function theory studies reveals that the unique features of Co@NC‐2ST enable a novel reaction route, that is, the CHO group of HMF is preferentially esterified instead of the OH group. This can be attributed to the nucleophilic addition reaction caused by the attack of methoxy anion on the CHO group of HMF. [ABSTRACT FROM AUTHOR]

• The quantum chemical calculations and ab initio dynamics simulation were adopted to clarify the gas phase and air-water interface reaction mechanisms of CH 3 CHOO and H 2 SO 4. • The reaction of CH 3 CHOO with H 2 SO 4 plays an active role in the CH 3 CHOO removal channel. • The formed interfacial CH 3 HC(OOH)OSO 3 − and H 3 O+ ions can attract candidate species for particle formation. • The oligomerization reaction of CH 3 CHOO with HPES in the gas phase is both thermochemically and kinetically favored • The reaction product can form stable clusters with sulfuric acids, ammonias and water molecules. The formation of oligomeric hydrogen peroxide triggered by Criegee intermediate maybe contributes significantly to the formation and growth of secondary organic aerosol (SOA). However, to date, the reactivity of C2 Criegee intermediates (CH 3 CHOO) in areas contaminated with acidic gas remains poorly understood. Herein, high-level quantum chemical calculations and Born-Oppenheimer molecular dynamics (BOMD) simulations are used to explore the reaction of CH 3 CHOO and H 2 SO 4 both in the gas phase and at the air-water interface. In the gas phase, the addition reaction of CH 3 CHOO with H 2 SO 4 to generate CH 3 HC(OOH)OSO 3 H (HPES) is near-barrierless, regardless of the presence of water molecules. BOMD simulations show that the reaction at the air-water interface is even faster than that in the gas phase. Further calculations reveal that the HPES has a tendency to aggregate with sulfuric acids, ammonias, and water molecules to form stable clusters, meanwhile the oligomerization reaction of CH 3 CHOO with HPES in the gas phase is both thermochemically and kinetically favored. Also, it is noted that the interfacial HPES− ion can attract H 2 SO 4 , NH 3 , (COOH) 2 and HNO 3 for particle formation from the gas phase to the water surface. Thus, the results of this work not only elucidate the high atmospheric reactivity of C2 Criegee intermediates in polluted regions, but also deepen our understanding of the formation process of atmospheric SOA induced by Criegee intermediates. [Display omitted] [ABSTRACT FROM AUTHOR]

A series of fused heterocyclic compound triazolotetrazine were prepared from the reaction of equimolar amount of 4-amino-5-phenyl-4H-1,2,4-triazole-3-thiol via cyclization addition reaction with different aromatic aldehydes in presence of piperidine as catalyst to produce the target [1,2,4]triazolo[4,3- b][1,2,4,5] tetrazine derivatives. The synthesized compounds were characterized by spectral methods (FT-IR and 1H-NMR, 13C-NMR and mass). The newly synthesized compounds exhibited an anticancer effect when these compounds were docked inside the C-Met tyrosine kinase receptor. As shown by their docking scores, they range from -5.599 to -4.403 Kcal/mol, whereas Crizotinib binding affinity is -3.211 Kcal/mol. For antibacterial efficiency, 4e and 4f testing on a series of bacteria, Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, and Klebsiella, respectively, reveals that the compounds have exhibited moderate activity against negative and positive bacteria. Antifungal activity of (4g, 4i) was assessed against the representative typical fungi such as Candidiasis fungal and compared with Fluconazole as an antifungal drugs. The results indicated that tested compounds had good fungicide activity, which has good growth inhibition against Candidiasis [ABSTRACT FROM AUTHOR]

AbstractThere have been studies published on the composition and coating uses of raw lacquers following enzymatic oxidative polymerization. The change of urushiol’ thermal stability and biological activity following polymerization to create oligomer, however, has received little attention. This work using silica gel column chromatography to separate urushiol and urushiol oligomer from polymerized raw lacquer and assessed its antibacterial, antioxidant, and thermal stability in an effort to decrease the allergenicity of urushiol and increase its application. By using gel chromatography, the urushiol oligomer were discovered to be polymers with 2–5 degrees of polymerization. According to characterization results from techniques like UV, FT-IR, and 1H NMR, urushiol was converted into urushiol oligomer by addition reactions, and C–C coupling. The findings demonstrated that the urushiol oligomer’ IC50 values for scavenging DPPH and ABTS free radicals were 40.8 and 27.4 μg/mL, respectively, and that their minimum inhibitory concentrations against Staphylococcus aureus and Staphylococcus epidermidis were 250 and 125 μg/mL. The urushiol oligomer’s thermogravimetric differential curve peak temperature (461.8 °C) was higher than urushiol’s (239.5 °C), indicating that urushiol undergoes polymerization with enhanced thermal stability. The study’s findings establish a foundation for the use of polymerized urushiol and urushiol oligomer in applications including functional materials and additives. [ABSTRACT FROM AUTHOR]

The fabrication of perovskite solar cells (PSCs) under full‐air conditions accelerates their scalable production and industrialization. However, ambient moisture interacts with perovskites during the film formation that disturbs their crystallization and triggers structural imperfections. Here, a formamidine (FA) active addition reaction (FAAR) strategy is devised to intercept the deleterious chemical coordination. The simultaneous incorporation of 2, 6‐bis(aminomethyl)pyridine (BAMPy) molecule into tin oxide surface and perovskite bulk ameliorates the interface contact and film interior. It is found that the tail amino group from BAMPy selectively reacts with FA cation, occupying A site of perovskite crystals, increasing binding energy of perovskite with H2O molecule even in a defective surface, thereby strengthening moisture tolerance. This strategy effectively modifies perovskite crystallization in ambient air, favors structural uniformity, and forms the compressive‐strained films. The FAAR‐modified PSC devices fabricated under full‐air conditions deliver the highest efficiencies of 24.11% and 21.68% with aperture areas of 0.06 and 1 cm2, respectively. The favorable moisture impediment property contributes to perovskite crystallization enhancement and structural uniformity, maintaining 90.8% of their initial performance for the encapsulated devices after 2400 h storage under accelerating damp‐heat measurements (85 °C and 85% relative humidity). [ABSTRACT FROM AUTHOR]

In this paper, a two‐step process is described for the chemoselective synthesis of highly fluorescent polycyclic chromeno[4,3,2‐ij]isoquinoline‐3‐carbonitriles using a sequential nucleophilic addition reaction involving 4‐chloro‐3‐vinyl coumarins, α,α‐dicyanoolefins and ammonium acetate as a source of nitrogen. In this process, it is believed that ammonium acetate is converted into ammonia and acetic acid during the reaction. Ammonia is the source of nitrogen, and the acid produced can catalyze the progress of the reaction. Single‐crystal X‐ray analysis was performed to confirm the structure of one of the typical products. In addition, the photophysical characteristics of the product 3 a were investigated through absorption and emission spectroscopy. This analysis reveals that the new heterocyclic system has impressive fluorescence characteristics. Several advantages of the presented synthetic strategy can be found in its simplicity, readily available starting materials, high‐efficiency products, highly chemoselective route, metal‐free catalyst, and ability to purify products by washing them with EtOH (96 %), a technique called GAP (Group‐Assisted‐Purification) chemistry. [ABSTRACT FROM AUTHOR]

Methylfluoride and hydrogen fluoride react with powerful methylating agent [SO2Me]+ in a temperature-dependent addition reaction to form methylated fluorosulfuric acid [FS(OMe)2][Sb2F11] and methylated fluorosulfuric acid methyl ester [FS(OH)(OMe)][SbF6], respectively. The obtained methylated fluorosulfinic acid and methylated fluorosulfinic acid methyl ester were characterized by single X-ray structure analysis and vibrational spectroscopy. [ABSTRACT FROM AUTHOR]

The catalytic decarboxylation of malonic acid half oxy‐ and thioesters, β‐ketocarboxylic acids, and their related compounds is a straightforward, powerful, and atom‐economical strategy for the in‐situ formation of enolates, which are important and well‐studied synthons for various functional materials and natural products. This strategy, inspired by the biosynthesis of polyketides and fatty acids, is an attractive method for synthesizing enols from carboxyl compounds with less reactive α‐hydrogen atoms under mild conditions. In addition, these reactions are environmentally friendly and are of great interest to chemists because the use of a stoichiometric amount of base can be avoided, and the only byproduct is CO2. Thus far, remarkable progress has been made, especially in the field of organocatalytic enantioselective decarboxylation reactions, allowing for the stereocontrolled formation of new C−H, C−C, C−heteroatom, and C−X bonds. This review provides a comprehensive overview of organocatalytic enantioselective decarboxylation reactions and highlights the significant progress made since 2020. In particular, it focuses on chiral catalyst systems and transition states as key parameters for decarboxylation reactions. [ABSTRACT FROM AUTHOR]

This paper describes a concise, asymmetric and stereodivergent total synthesis of tacaman alkaloids. A key step in this synthesis is the biocatalytic Baeyer–Villiger oxidation of cyclohexanone, which was developed to produce seven‐membered lactones and establish the required stereochemistry at the C14 position (92 % yield, 99 % ee, 500 mg scale). Cis‐ and trans‐tetracyclic indoloquinolizidine scaffolds were rapidly synthesized through an acid‐triggered, tunable acyl‐Pictet–Spengler type cyclization cascade, serving as the pivotal reaction for building the alkaloid skeleton. Computational results revealed that hydrogen bonding was crucial in stabilizing intermediates and inducing different addition reactions during the acyl‐Pictet–Spengler cyclization cascade. By strategically using these two reactions and the late‐stage diversification of the functionalized indoloquinolizidine core, the asymmetric total syntheses of eight tacaman alkaloids were achieved. This study may potentially advance research related to the medicinal chemistry of tacaman alkaloids. [ABSTRACT FROM AUTHOR]

Superhydrophobic materials used for oil–water separation have received wide attention. However, the simple and low‐cost strategy for making durable superhydrophobic materials remains a major challenge. Here, this work reports that stable and durable superhydrophobic cotton fabrics can be prepared using a simple two‐step impregnation process. Silica nanoparticles are surface modified by hydrolysis condensation of 3‐aminopropyltrimethoxysilane (APTMS). 1,4‐conjugate addition reaction between the acrylic group of cross‐linking agent pentaerythritol triacrylate (PETA) and the amino group of octadecylamine (ODA) forms a covalent cross‐linked rough network structure. The long hydrophobic chain of ODA makes the cotton fabric exhibit excellent superhydrophobic properties, and the water contact angle (WCA) of the fabric surface reaches 158°. The modified cotton fabric has good physical and chemical stability, self‐cleaning, and anti‐fouling. At the same time, the modified fabric shows excellent oil/water separation efficiency (98.16% after 20 cycles) and ultrahigh separation flux (15413.63 L m−2 h−1) due to its superhydrophobicity, superoleophilicity, and inherent porous structure. The method provides a broad prospect in the future diversification applications of oil/water separation and oil spill cleaning. [ABSTRACT FROM AUTHOR]

Reactive melt infiltration (RMI) is a typical method to produce carbon fiber-reinforced ultra-high temperature ceramic matrix composites (C f /UHTCs), for which the molten Si is a very general and practical infiltrator. High-entropy carbide (HE-carbide) is a newly developed promising matrix phase of C f /UHTCs. Understanding the phase equilibrium relation in the HE-carbide and Si reaction system can provide accurate guidance on designing the RMI process for preparing HE-carbide matrix composites with controlled phases and microstructure. This study systematically investigates W-containing HE-carbide and Si addition reactions at high temperatures. Samples with nominal starting compositions of (Ti 0. 2 Zr 0.2 Hf 0.2 Ta 0. 2 W 0.2)C- x Si (HEC- x Si, x = 2.5, 5 and 10 wt%) are prepared by spark plasma sintering technique at 1500 °C and 1700 °C with an axial pressure of 40 MPa for 10 min. The results show that adding 2.5 wt% or 5 wt% Si removes carbon from the HEC matrix, forming SiC and stable equimolar (Ti 0. 2 Zr 0.2 Hf 0.2 Ta 0. 2 W 0.2)C 1- x phase with carbon deficiency at high temperatures. In contrast, besides the SiC phase, the addition of 10 wt% Si in the HEC matrix may form unstable transient phases of (Ti 0. 2 Zr 0.2 Hf 0.2 Ta 0. 2 W 0.2)C 1- x with supersaturated carbon deficiencies at high temperatures, which finally decomposes into non-equimolar HE-carbide (Ti 0. 2 Zr 0.2 Hf 0.2 Ta 0. 2 W 0.2- y)C 1- z and metal silicide WSi 2 phases. The effects of the HEC and Si reactions on the microstructure evolution of the samples during sintering are discussed. Meanwhile, the mechanical properties of the samples with the reaction resulting microstructure are measured and briefly discussed. [ABSTRACT FROM AUTHOR]

We have developed radical C‐glycosylation using photoexcitable unprotected glycosyl borate. The direct excitation of glycosyl borate under visible light irradiation enabled the generation of anomeric radical without any photoredox catalysts. The in situ generated anomeric radical was applicable to the radical addition such as Giese‐type addition and Minisci‐type reaction to introduce alkyl and heteroaryl groups at the anomeric position. In addition, the radical–radical coupling between the glycosyl borate and acyl imidazolide provided unprotected acyl C‐glycosides. [ABSTRACT FROM AUTHOR]

A novel synthetic route has been designed to introduce fluorine functionality into a series of compounds containing thiazolidin-4-one rings. These compounds were synthesised from various aniline derivatives using a two-step approach: an addition reaction of ethyl isothiocyanate with different aromatic fluorinated anilines, followed by cyclisation to yield the final products. A total of 15 novel fluorinated thiazolidinone compounds were synthesised and characterised using 1H NMR, 19F NMR, Fourier transform–infrared, elemental analysis and liquid chromatography–mass spectrometry. Stereochemistry around the imine bond in the synthesised derivatives was determined using nuclear Overhauser effect spectroscopy. The in vitro anticancer potential of the compounds was tested against two human cancer cell lines, liver (HepG2) and colon (HCT116). The study revealed that the derivatives having fluorine functionality at both the m- positions in the aromatic ring showed promising anticancer potential, as compared to those at o- and p- positions. A series of thiourea intermediates were prepared by addition reaction between various aniline derivatives and ethyl isothiocyanate. These intermediates were further cyclised with the help of ethyl bromofluoroacetate to yield fluorinated thiazolidin-4-one derivatives. The anticancer activities of these novel fluorinated moieties against human liver and colon cancer cell lines have been investigated. (Image credit: Shreyash Kadam.) [ABSTRACT FROM AUTHOR]

This article describes the synthesis of a hydrophobic protective coating for concrete based on a silane derivative of fatty acids. The coating was obtained through a thiol-ene click addition reaction using methyl oleate and 3-mercaptopropyltrimethoxysilane in the presence of the photoinitiator 2,2-dimethoxy-2-phenylacetophenone (DMPA). This reaction proved to be more efficient compared with other tested (photo)initiators, considering the double bond conversion of oleate. The coating was applied to concrete using two methods: immersion and brushing. Both methods exhibited similar consumption of methyl oleate-based silane (UVMeS) at approximately 20 g/m2. The hydrophobic properties of the coatings were evaluated based on the contact angle, which for the modified surfaces was above 93°, indicating their hydrophobic nature. The penetration depth of the silane solution into the concrete was also studied; it was 5–7 mm for the immersion method and 3–5 mm for the brushing method. The addition of tetraethoxysilane (TEOS) to the silane solution slightly improved the barrier properties of the coating. [ABSTRACT FROM AUTHOR]

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Synthesis of novel unnatural amino acids (UAAs) from 4‐oxo‐4‐phenylbut‐2‐enoic acid derivatives with intramolecular aza‐Michael addition reaction in the presence of chlorosulfonyl isocyanate (CSI) was reported in soft conditions without any metal catalyst. Acids and base as a catalyst, and solvents effects were investigated for the synthesis of novel UAAs. This novel method provides inexpensive, practicable, and efficient approach to generate UAAs. The use of UAAs has attracted great interest in the development of therapeutic agents and drug discovery to improve their properties. In this context, in addition to the synthesis of new UAAs, their inhibition effects on important metabolic enzymes of acetylcholinesterase (AChE) and carbonic anhydrases I and II (hCA I and II) enzymes were investigated. The compound 2g showed the best inhibition for CA I and AChE enzymes, while compound 2i exhibited the best inhibition profile against CA II isoenzyme. The inhibition values of these compounds were found as 1.85 ± 0.64 for AChE, 0.53 ± 0.07 for hCA I, 0.44 ± 0.15 µM for hCA II, respectively, and they showed a stronger inhibitory property than acetazolamide (standard inhibitor for hCA I and II) and tacrine (standard inhibitor for AChE) molecules. The activity of the studied molecule against different proteins that are hCA I (PDB ID: 2CAB), hCA II (PDB ID: 5AML), and AChE (PDB ID: 1OCE) was examined. Finally, the drug properties of the studied molecule were examined by performing absorption, distribution, metabolism, excretion, and toxicity analysis. [ABSTRACT FROM AUTHOR]