The cover image is based on the Research Article Solvent effects on the sodium borohydride reduction of 2-halocyclohexanones by Daniela Rodrigues Silva, Lucas A. Zeoly, Pascal Vermeeren, Rodrigo A. Cormanich, Trevor A. Hamlin, Célia Fonseca Guerra and Matheus P. Freitas, https://doi.org/10.1002/poc.4556.
![Influence of external electric field on structure, spectra and various properties of 3-Chlorothieno[2,3-b]pyridine-2-carbonitrile using density functional theory](https://onlinelibrary.wiley.com/cms/asset/daa34e91-164b-4bbe-b57a-f3c8e7262733/poc4554-toc-0001-m.png)
The structure, total energy, dipole moment, Hirshfeld charge, molecular electrostatic potential, infrared, Raman, and UV-Vis spectra of 3-chlorothieno[2,3-b]pyridine-2-carbonitrile (CPC) under EEF through density functional theory. The calculations indicated that the bond length, the bond angle, total energy, dipole moment, and energy gap of CPC are strongly affected by EEF. Infrared, Raman, and UV-Vis spectra showed stark vibration effect with the increasing EFF. Our results provide a basis for further applications of CPC with and without EEF.
Thiophene and pyridine compounds are widely used in medicine, pesticides, and material fields, and study of their physical and chemical changes under an external electric field (EEF) will improve a deep understanding of their properties. In this work, we selected 3-Chlorothieno[2,3-b]pyridine-2-carbonitrile (CPC) as the representative and explored the structure, total energy, dipole moment, Hirshfeld charge, molecular electrostatic potential, infrared, Raman, and UV-Vis spectra of CPC under EEF through density functional theory (DFT). The calculations indicated that the bond length, the bond angle, total energy, dipole moment, and energy gap of CPC are strongly affected by EEF. Infrared, Raman, and UV-Vis spectra showed stark vibration effects with increasing EFF. Our results provide a basis for further applications of CPC with and without EEF.
Structure–activity relationship of alkanes and derivatives for the abilities of C(sp3)H bonds toward their H-atom transfer reactions is researched by bond dissociation free energy ΔG o(XH), intrinsic resistance energy ΔG ≠ XH/X, and thermo-kinetic parameter ΔG ≠o(XH).
Hydrogen atom-donating ability of alkane is a research hotspot and has been extensively studied. In this article, the second-order rate constants of 20 hydrogen atom transfer (HAT) reactions between aliphatic, benzylic, and allylic alkanes and alkane derivatives with CumO• in acetonitrile at 298 K were studied. The thermo-kinetic parameter ΔG ≠o(XH), bond dissociation free energy ΔG o(XH), and kinetic intrinsic resistance energy ΔG ≠ XH/X were determined and used to evaluate the H-donating abilities of these substrates in thermodynamics, kinetics, and HAT reactions. Structure–activity relationships including the factors (electronic, stereoelectronic, and steric effects), introduction of CH3, Ph, or Cl in alkanes, and introduction of N atom in cycloalkane were discussed carefully. The results show that the order of H-donating abilities is allylic alkanes > cycloalkanes > chain alkanes ≈ benzylic alkanes > haloalkanes. The introduction of CH3, Ph, or Cl in alkanes and the introduction of N atom to the carbon ring reduce ΔG o(XH) but increase ΔG ≠ XH/X, and ΔG ≠o(XH) is the synthesis result of these two parameters. The reliability of ΔG ≠o(XH) was verified, and the accuracy and reliability of the parameters were proved. Through the study of this paper, not only the ΔG o(XH), ΔG ≠ XH/X, and ΔG ≠o(XH) of these alkanes and derivatives in HAT reaction can be quantitatively evaluated but also the structure–activity relationship of alkane is clearly researched.
Benzofuran-based building blocks are used as a standard molecule to search for new building blocks. Similarity analysis is performed to screen/search potential candidates for photodetectors based on the chemical structural similarity. Extended-connectivity fingerprints (ECFPs) are used for the similarity analysis. The virtual libraries of unique monomers are enumerated. The breaking retro-synthetically interesting chemical substructures (BRICS) method is used to design building blocks by automatically decomposing and combining monomers in enumerated libraries.
Organic molecules have been extensively utilized in various applications including materials science, chemical, and biomedical fields. Traditionally, the design of organic molecules is achieved through experimental approaches, guided by conceptual insights, intuition, and experience. Although these experimental approaches have been successfully utilized to unveil various high-performance materials, these methods show serious limitations due to vast design space and the ever-increasing demand for organic molecules (new materials). Artificial intelligence with computer science is used by modern researchers to design materials with better performance and for predicting the properties of new materials. Herein, benzofuran-based building blocks are used as a standard molecule to search for new building blocks. Similarity analysis is performed to screen/search potential candidates for photodetectors based on the chemical structural similarity. Extended-connectivity fingerprints (ECFPs) are used for the similarity analysis. The virtual libraries of unique monomers are enumerated. The breaking retro-synthetically interesting chemical substructures (BRICS) method is also used to design building blocks by automatically decomposing and combining monomers in enumerated libraries. Moreover, this work offers a potential way to identify new monomers for photodetectors cost-effectively and rapidly.
Experimental and theoretical studies on the OH + CH2 = CHCH2Br reaction have been performed. New pathways have been proposed in the mechanisms. Canonical variational transition state theory had a good performance predicting experimental results.
In this work, the rate-determining steps of the OH radical + 3-bromopropene gas phase reaction were studied, which could explain for the possible negative activation energy observed in experiments. To obtain new kinetic parameters and data for critical revisions, a reinvestigation of the rate coefficient (k) and its temperature dependence was carried out using the PLP-LIF technique, in the 254- to 371-K range. Moreover, quantum-mechanical and canonical variational transition state theory calculations were performed, taking into consideration four OH addition and two β-hydrogen atom abstraction reaction channels. The proposed kinetic model fits to the observed experimental Arrhenius behavior, and three not negligible reaction pathways are described for the first time.
2-Halocyclohexanones are more reactive than cyclohexanone itself, and the main product is cis. However, only microsolvation could properly model the reduction reaction pathway involving the polar transition states.
We have investigated the stereoselectivity and reactivity of the sodium borohydride reduction of 2-X-cyclohexanones (X=H, Cl, Br) using a combined approach of competitive experiments and density functional theory calculations. Our results show that the hydride addition proceeds via a late transition state in which the C–H bond is nearly formed, consistent with the mild reducing power of NaBH4. The reaction barrier decreases from the 2-halocyclohexanones to the unsubstituted cyclohexanone, in line with relative reactivities observed in the competitive experiments. Furthermore, we provide a protocol to solve the longstanding issue of properly modelling the axial–equatorial facial selectivity of hydride addition to the carbonyl group substituted with a vicinal polar group. The inclusion of implicit solvation in combination with an explicit solvent molecule is crucial to reproduce the stereoselective formation of the cis product observed experimentally.
Heterocycles and barbituric acid analogs are particularly used in developing and designing new drugs because of their versatile binding properties for different biotargets. They are present in many natural compounds, vitamins, drugs, and biologically active molecules such as anticancer, antibiotic, antidiabetic, anti-inflammatory, antidepressant, anti-HIV, antimicrobial, and insecticidal agents. Using co-friendly techniques under nanocatalyst conditions drives the synthesis of these bioactive compounds toward green chemistry. This review will investigate the nanocatalysts, including magnetic nanocatalysts, nano metal-based catalysts, organo-nanocatalysts, and metal–organic frameworks (MOFs) nanocatalysts employed in the synthesis and design of heterocyclic compounds by barbituric acids from 2017 to 2022.
Heterocycles and barbituric acid analogs are particularly used in developing and designing new drugs because of their versatile binding properties for different biotargets. They are present in many natural compounds, vitamins, drugs, and biologically active molecules such as anticancer, antibiotic, antidiabetic, anti-inflammatory, antidepressant, anti-HIV, antimicrobial, and insecticidal agents. Using co-friendly techniques under nanocatalyst conditions drives the synthesis of these bioactive compounds toward green chemistry. This review will investigate the nanocatalysts, including magnetic nanocatalysts, nano metal-based catalysts, organo-nanocatalysts, and metal–organic frameworks (MOFs) nanocatalysts employed in the synthesis and design of heterocyclic compounds by barbituric acids from 2017 to 2022.
Organic materials with Inverted Singlet-Triplet (INVEST) gaps are interesting for their potential use as photocatalytic small molecule transformations, like the entirely solar-driven water splitting reaction. However, only few INVEST emitters are thermodynamically able to split water, with first singlet excited states, S1, above 1.27 or 1.76 eV; and absorbing near solar maximum, 2.57 eV. These requirements and the INVEST character are key for achieving long-lived photocatalyst for water splitting. The only known INVEST emitters that conform to these criteria are large triangular boron carbon nitrides, with unknown synthesis pathways. With quantum-mechanical calculations using ADC(2), we describe three triangulenes. 3a is a cyano azacyclopenta[cd]phenalene derivative while 3b and 3c are cycl[3.3.3]azine derivatives. 3b has a previously undescribed disulfide bridge. Overall 3a fulfills requirements for photocatalytic four-electron reduction of water while the S1 states of 3b and 3c are likely slightly low for the two-electron reduction process. By analyzing impacts of ligands, we find that there are guidelines describing how S1-S5 energies and oscillator strengths, T1 energies and ΔES1T1 gaps are affected, requiring deep-learning algorithms for which studies will be presented by us in due time. The impact of solvation effects as well as reduced-cost ADC(2) algorithms on our findings are discussed.
The practical implementation of the lithium metal anode (LMA) has long been pursued due to its extremely high specific capacity and low electrochemical equilibrium potential. However, the unstable interfaces resulting from lithium ultrahigh reactivity have significantly hindered the use of LMA. This instability directly leads to dendrite growth behavior, dead lithium, low Coulombic efficiency, and even safety concerns. Therefore, artificial solid electrolyte interfaces (ASEI) with enhanced physicochemical and electrochemistry properties have been explored to stabilize LMA. Polymer materials, with their flexible structures and multiple functional groups, offer a promising way for structurally designing ASEIs to address the challenges faced by LMA. This Concept demonstrates an overview of polymer ASEIs with different functionalities, such as providing uniform lithium ion and single-ion transportation, inhibiting side reactions, possessing self-healing ability, and improving air stability. Furthermore, challenges and prospects for the future application of polymeric ASEIs in commercial lithium metal batteries (LMBs) are also discussed.
Nanogels represent promising drug delivery systems in the biomedical field, designed to overcome challenges associated with standard treatment approaches. Stimuli-responsive nanogels, often referred to as intelligent materials, have garnered significant attention for their potential to enhance control over properties such as drug release and targeting. Furthermore, researchers have recently explored the application of nanogels in diverse sectors beyond biomedicine including sensing materials, catalysts, or adsorbents for environmental applications. However, to fully harness their potential as practical delivery systems, further research is required to better understand their pharmacokinetic behaviour, interactions between nanogels and bio distributions, as well as toxicities. One promising future application of stimuli-responsive multifunctional nanogels is their use as delivery agents in cancer treatment, offering an alternative to overcome the challenges with conventional approaches. This review discusses various synthetic methods employed in developing nanogels as efficient carriers for drug delivery in cancer treatment. The investigations explore, the key aspects of nanogels, including their multifunctionality and stimuli-responsive properties, as well as associated toxicity concerns. The discussions presented herein aim to provide the readers a comprehensive understanding of the potential of nanogels as smart drug delivery systems in the context of cancer therapy.