A conceptual DFT analysis of the plausible mechanism of some pericyclic reactions

Morales‐Bayuelo, Alejandro; Sánchez‐Márquez, Jesús; Jana, Gourhari; Chattaraj, Pratim Kumar

doi:10.1007/s11224-020-01527-7

Cited by 11 publications

(13 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Using such studies has led to the postulation of electronic reorganizations through a pseudodiradical character and not the pericyclic reorganization postulated by Woodward-Hoffmann (WH) [ 29 , 30 ] and showing to the Diels-Alder reactions as {2n + 2π} pseudodiradical cycloadditions [ 31 , 32 ]. Moreover, in recent years our research group has studied electron reorganization using the ELF context, getting similar results about the pseudodiradical character [ 33a )]. Additionally, we used the quantum theory of atoms in molecules (QTAM), natural bond orbital frameworks, and electronic structure principles such as maximum hardness, minimum electrophilicity and minimum polarizability to seek new insights into the electronic reorganization process according to experimental data [( 33c-d )].…”

Section: Introductionmentioning

confidence: 94%

“…Moreover, in recent years our research group has studied electron reorganization using the ELF context, getting similar results about the pseudodiradical character [ 33a )]. Additionally, we used the quantum theory of atoms in molecules (QTAM), natural bond orbital frameworks, and electronic structure principles such as maximum hardness, minimum electrophilicity and minimum polarizability to seek new insights into the electronic reorganization process according to experimental data [( 33c-d )].…”

Section: Introductionmentioning

confidence: 94%

See 1 more Smart Citation

Discerning the thermal cyclotrimerizations of fluoro- and chloroacetylenes through ELF, NBO descriptors and QTAIM analysis: pseudodiradical character

Morales-Bayuelo

Sánchez‐Márquez

2020

Heliyon

Self Cite

View full text Add to dashboard Cite

In this study the thermal cyclotrimerization reactions of fluoro- and chloroacetylenes involving regioselectively stepwise {2 + 2} and stepwise {4 + 2} cycloadditions were studied using the topological analysis of the electron localization function (ELF), the quantum theory of atoms in molecules (QTAIM) and natural bond orbital (NBO) analyses. These methodologies have shown that the electronic reorganization in the regioselectively stepwise {2 + 2} and stepwise {4 + 2} cycloadditions may be considered as {2n+2n} and {2π+2n} pseudodiradical process, respectively. Finally, the last phase of this thermal reaction can be understood as an electronic migration process under the pseudodiradical character in the thermal ring-opening reaction, with the subsequent formation of reaction products. In this sense, new insights are reported on the electronic behavior in the bond formation in the thermal cyclotrimerization of fluoroacetylene.

show abstract

Section: Introductionmentioning

confidence: 94%

Section: Introductionmentioning

confidence: 94%

Discerning the thermal cyclotrimerizations of fluoro- and chloroacetylenes through ELF, NBO descriptors and QTAIM analysis: pseudodiradical character

Morales-Bayuelo

Sánchez‐Márquez

2020

Heliyon

Self Cite

View full text Add to dashboard Cite

show abstract

“…[1][2][3][4] Modeling is exceptionally efficient in deciphering reaction mechanisms. [5][6][7][8][9][10][11][12][13][14] Isoxazole ring is a key structural moiety of valuable pharmaceutical substances (Figure 1). [15] Among them are antibiotics, [16][17][18][19] as cloxacillin, [16,18,20] dicloxacillin [16,18,[20][21][22] and flucloxacillin, [16,18,20,23,24] which were included in the WHO Model List of Essential Medicines and recommended for the treatment of a wide range of bacterial infections.…”

Section: Introductionmentioning

confidence: 99%

Negligible Substituent Effect as Key to Synthetic Versatility: a Computational‐Experimental Study of Vinyl Ethers Addition to Nitrile Oxides

et al. 2022

View full text Add to dashboard Cite

A tangible substituent effect may be perceived as a good feature in developing an organic reaction. This work demonstrates that, on the contrary, a zero-slope Hammet plot should be sought. The synthesis of isoxazoles by consecutive cycloaddition of nitrile oxides to vinyl ethers and alcohols elimination was studied computationally and experimentally. We performed a Hammett study in silico to demonstrate a negligible substituent effect (i. e., broad substrate scope) in the addition of benzyl vinyl ether to nitrile oxides. The modeling was performed at the ωB97X-V/def2-TZVP//PBE0-D4/def2-TZVP + SMD(benzene) level of theory within the RIJCOSX approximation. The experimental evaluation validated the computational model. A versatile methodology for synthesizing substituted isoxazolines and isoxazoles was proposed as the main result. We present this work as a successful example of how quantum chemical modeling can re-boost the classic Hammett approach to the optimization and design of organic synthetic methodologies. We anticipate further Hammett studies in silico, considering the current trend for data-driven chemical research.

show abstract

“…(WH) [ 26 , 27 ] and showed the electrocyclic reactions as pseudodiradical ring opening reactions {2n + 2π} [ 28 , 29 ]. In addition, we use the analysis of natural bond orbitals (NBO), the quantum theory of atoms in molecules (QTAM), and the electronic structure principles such as minimum polarisability, minimum electrophilicity and maximum hardness, to find new insights into the process of electronic rearrangement in accordance with experimental data [ 30 , 31 , 32 , 33 ].…”

Section: Introductionmentioning

confidence: 99%

New insights about electronic mechanism of electrocyclic reactions: theoretical study about stereoselectivity in cyclobutenes

Morales-Bayuelo

Sánchez‐Márquez

2021

Heliyon

Self Cite

View full text Add to dashboard Cite

This work presents the study of a series of electrocyclic reactions with the main aim of obtaining new insights into the reaction process along IRCs. The energy variation of the different reaction paths as well as the different transition states have been calculated. These trends are according to the experimental data. The natural bond orbitals have been obtained and the second order perturbational theory analysis has been carried out to determine the main charge transfers due to delocalization. Bond reactivity indexes have been used to describe the reactivity mechanism in a local way. These reactivity indexes are also based on NBOs and this has made it possible to connect the results of the indexes with the previous analysis. To determine quantitatively the bond structure, we used the quantum theory of atoms in molecules and we have hereby completed the information obtained from the NBO analysis. Finally, we used the Hirshfeld population analysis as an approximation to understand how the load density changes in the different reaction pathways, and we have connected these variations with the information obtained from the bond structure. The results has found that the reaction path with the lowest energy barrier Transition State Inward Conrotatory (TSIC) or Transition State Outward Conrotatory (TSOC) is determined by two magnitudes: the charge donations by delocalisation of the substituents (which we obtained from the Second Order Perturbational Theory Analysis of the NBOs) and in the case that these donations were very similar, the non-covalent interactions dominated (which we studied by means of the interaction energies of the Hirshfeld charges). Additionality, the most important factor influencing the lower energy reaction path was the interaction of lone pairs of the substituents with the σ∗(C–C) bond that is broken at the opening of the cycle. The alignment of these lone pairs with the C–C bond favours charge donation between them and, as can be seen in the discussion, this alignment varies depending on whether the structure is TSIC and TSOC.

show abstract

A conceptual DFT analysis of the plausible mechanism of some pericyclic reactions

Cited by 11 publications

References 57 publications

Discerning the thermal cyclotrimerizations of fluoro- and chloroacetylenes through ELF, NBO descriptors and QTAIM analysis: pseudodiradical character

Discerning the thermal cyclotrimerizations of fluoro- and chloroacetylenes through ELF, NBO descriptors and QTAIM analysis: pseudodiradical character

Negligible Substituent Effect as Key to Synthetic Versatility: a Computational‐Experimental Study of Vinyl Ethers Addition to Nitrile Oxides

New insights about electronic mechanism of electrocyclic reactions: theoretical study about stereoselectivity in cyclobutenes

Contact Info

Product

Resources

About