Synthesis, structural and computational studies of new tetrazole derivatives

Oklješa, Aleksandar M.; Klisurić, Olivera R.

doi:10.1016/j.molstruc.2020.129341

Cited by 10 publications

(4 citation statements)

References 49 publications

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“…In the 1 H NMR spectrum of the product, the methyl protons appear at 2.55 ppm (vs 2.49 ppm in 5‐methyl‐1H‐tetrazole); [33] thus not in the anisotropic region of the bottom ring. It suggests that treating 17 with sodium azide in refluxing acetonitrile produced compound 18 as its A rotamer (Scheme 10).…”

Section: Resultsmentioning

confidence: 97%

Through‐Space, Lone‐Pair Promoted Aromatic Substitution: A Relay Mechanism Can Beat Out Direct Activation

Kazim

Feng

Vemulapalli

et al. 2023

Chemistry A European J

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We report a detailed experimental and theoretical analysis of through‐space arene activation with halogens, tetrazoles and achiral esters and amides. Contrary to previously assumed direct activation through σ‐complex stabilization, our results suggest that these reactions proceed by a relay mechanism wherein the lone pair‐containing activators form exothermic π‐complexes with electrophilic nitronium ion before transferring it to the probe ring through low barrier transition states. Noncovalent interactions (NCI) plots and Quantum Theory of Atoms in Molecules (QTAIM) analyses depict favorable interactions between the Lewis base (LB) and the nitronium ion in the precomplexes and the transition states, suggesting directing group participation throughout the mechanism. The regioselectivity of substitution also comports with a relay mechanism. In all, these data pave the way for an alternate platform of electrophilic aromatic substitution (EAS) reactions.

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Section: Resultsmentioning

confidence: 97%

Through‐Space, Lone‐Pair Promoted Aromatic Substitution: A Relay Mechanism Can Beat Out Direct Activation

Kazim

Feng

Vemulapalli

et al. 2023

Chemistry A European J

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“…Quantum calculations including molecular electrostatic potential (MEP) and binding energy were utilized to find out the reason for the different chemical stabilities among NIC-OA polymorphs and NIC. MEP has been widely used to explore the weak interaction sites in crystal engineering , and distinguish the electrophilic and nucleophilic regions in molecules . Herein, the structure of NIC and the asymmetric unit of each NIC-OA salt polymorph both in vacuum (Figure ) and in the conformations optimized in water (Figure S12) were analyzed.…”

Section: Resultsmentioning

confidence: 99%

Insight into the Structure and Property Diversity of Four Nicorandil Oxalate Salt Polymorphs Based on Experiments and Quantum Chemistry Study

Wang,

Guo,

et al. 2024

Crystal Growth & Design

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This contribution presents a novel and comparative study on the relationship between the crystal structure and the property diversity of a complex polymorph system of nicorandil oxalate (NIC-OA) salts. Single-crystal structures of four salt polymorphs with 1:1 stoichiometry were prepared, and crystal structure analysis revealed the difference of configuration and tautomer structure among those polymorphs. Bulk samples of three polymorphs (S1, S3 and S4) were successfully isolated from ethanol/water solution, while the metastable form S2 could not be obtained. Detailed property studies including solvent-mediated polymorph transformation, physical-chemical stability, and intrinsic dissolution of those polymorphs were conducted. Phase transformation from S3 to S4 in high-humidity conditions and accelerated conditions was driven by lowering of lattice energy. High hygroscopicity would accelerate the process. All polymorphs showed better chemical stability and greater dissolution rate compared to NIC. The binding energy between NIC and oxalate acid and crystal-solvent interaction were studied to investigate the correlation between polymorph packing and bulk property. The chemical stability of NIC was affected by the diversity in cation–anion binding modes, while the dissolution process of the polymorphs was influenced by the crystal face differences and the interaction between the crystal and solvent. It is the first time that four crystalline forms of NIC-OA are reported, and the structure and property diversity among these salt polymorphs are revealed with experiments and the quantum chemistry method, which provided new insights into the NIC-OA polymorphs in the crystal engineering field and might contribute to the property research of the complex pharmaceutical polymorphism system.

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“…The HOMO/LUMO energy gap constitutes a critical parameter in determining, for instance, molecular electrical transport properties [18,19]. The global chemical reactivity descriptors calculated for the ( E ) and ( Z ) isomer of the title compound using DFT are: electron affinity (A), chemical potential (μ), ionization potential (IP), chemical hardness (η), electronegativity (χ), and electrophilicity (ɷ), (Table 5) [20]. The calculated energy gap between HOMO and LUMO of the ( E ) isomer is 0.1132 Hartree (3.0811 eV), while for the ( Z ) isomer, it is larger with 0.12022 Hartree (3.2715 eV) demonstrating that the ( Z ) isomer is harder, more stable, and less reactive than the ( E ) isomer.…”

Section: Resultsmentioning

confidence: 99%

Crystal structure and quantum chemical calculations of (E)1‐benzyl‐3‐((4‐methoxyphenyl)imino)‐5‐methylindolin‐2‐one

El-wahab

Hamdy

Schulzke

et al. 2021

Journal of Heterocyclic Chem

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The known Schiff base compound, (E)1‐benzyl‐3‐((4‐methoxyphenyl)imino)‐5‐methylindolin‐2‐one, was prepared as before by reacting 1‐benzyl‐5‐methylindoline‐2,3‐dione with 4‐methoxyaniline. The product was unambiguously characterized using elemental analysis, 1H and 13C‐NMR spectroscopy, and its new single‐crystal X‐ray structural analysis. Molecular orbital calculations were conducted in order to investigate the structures and relative stabilities of the (E) and (Z) isomers of 1‐benzyl‐3‐([4 methoxyphenyl]‐imino)‐5‐methylindolin‐2‐one. Specific attention was paid to the (E) isomer. The available crystallographic experimental data for the latter ensured also validation of the model structures computationally derived at the theoretical B3LYP/6‐31G(d,p) level.

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Synthesis, structural and computational studies of new tetrazole derivatives

Cited by 10 publications

References 49 publications

Through‐Space, Lone‐Pair Promoted Aromatic Substitution: A Relay Mechanism Can Beat Out Direct Activation

Through‐Space, Lone‐Pair Promoted Aromatic Substitution: A Relay Mechanism Can Beat Out Direct Activation

Insight into the Structure and Property Diversity of Four Nicorandil Oxalate Salt Polymorphs Based on Experiments and Quantum Chemistry Study

Crystal structure and quantum chemical calculations of (E)1‐benzyl‐3‐((4‐methoxyphenyl)imino)‐5‐methylindolin‐2‐one

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