Impact of Global and Local Reactivity Descriptors on the Hetero-Diels-Alder Reaction of Enaminothione With Various Electrophiles

Abstract

The mechanism of the Diels-Alder reaction of 1-(2-furyl)-3-(dimethylamino)-2-propene-1-thione with various dienophiles resulting in the formation of 2H-thiopyran derivatives were discussed by evaluating global and local electrophilicity and nucleophilicity descriptors for whole series of diene and dienophiles at B3LYP/6-31G* level of theory. The results preluded that the polarity and charge transfer flow between diene and dienophiles was consistent with the global reactivity descriptors and substitutional pattern. The local descriptors based on Parr functions proposed by Domingo were found to be quite promising to explain the regioselectivity of cycloaddition processes. For symmetrical dienophiles viz., 2, 5, 8, 11a, 11b, 13 and 14 the local descriptors concentrates equally (50%) at both interacting sites, to allocate non-regioselective cycloadditions. However, unsymmetrical dienophiles 16,18a-e and 21 have shown a preference towards a particular regioisomer and shown high regioselectivity during cycloaddition reaction. Regional nucleophilicity at the interacting site of diene were evaluated using local nucleophilicity descriptor N k . These outcomes were found to be in exact correlation with the experimental outcomes achieved by Bogdanowicz et al.

Anthrone‐Benzothiazole Based Heterocyclic Disperse Azo Dyes: Synthesis, Dyeing, UV Protection Property, Anti‐Bacterial Activity, and Computational Study

“…The chemical potential (μ), chemical hardness (η), and global softness (S) of a molecule are calculated using Koopman's theorem (Eq. (5), (6), (7)) (Table 7): [49] $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr \mu =-{{1}\over{2}}\ ({{\rm E}}_{HOMO}+{{\rm E}}_{{\rm L}{\rm U}{\rm M}{\rm O}})\ \hfill\cr}}$$$ $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr \eta ={{1}\over{2}}\ ({{\rm E}}_{LUMO}-{{\rm E}}_{{\rm H}{\rm O}{\rm M}{\rm O}})\ \hfill\cr}}$$$ $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr S={{1}\over{{\rm \eta }}}\ \hfill\cr}}$$$ …”

“…where, μ = chemical potential; η = chemical hardness The chemical potential (μ), chemical hardness (η), and global softness (S) of a molecule are calculated using Koopman's theorem (Eq. ( 5), ( 6), ( 7)) (Table 7): [49]…”

QSAR Modeling, Molecular Docking and Cytotoxic Evaluation for Novel Oxidovanadium(IV) Complexes as Colon Anticancer Agents

“…The highest value appeared with the VO-CTZ complex (5.03 eV), followed by VO-SCZ and VO-CBZ, which reveal their biological potency. The ∆N max is an expression of the maximum charge an electrophile may accept from the environment [44]. We could arrange the metal complexes depending on this value in descending order, VO-CTZ > VO-LOR > VO-SCZ > VO-CBZ, which represents the capacity of VO-CTZ to be an anticancer agent.…”

Substituent Effects in 3,3’ Bipyrazole Derivatives. X-ray Crystal Structures, Molecular Properties and DFT Analysis

“…, 37 Finally, the global electrophilicity index (ω) gives a measure of the stabilization energy involved in a process during which a molecule acquires an additional electronic charge from its environment. 38 It is interesting to note that a correlation has been established between the electrophilic index and the toxicity 39 and that the organic compounds with the highest electrophilicity indices would be the most toxic. Moreover, it has been stated that the global electrophilicity index provides information about the electrophilic or nucleophilic nature of a medicinal compound.…”