9 A computational study of the SNAr reaction of 2-ethoxy-3,5-dinitropyridine and 2-methoxy-3, 5-dinitropyridine with piperidine
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Oluwakemi A. Oloba-Whenu
Abstract
A computational study of the chemical kinetics and thermodynamics study of the SNAr between 3,5-dinitroethoxypyridine 1a and 3,5-dinitromethoxypyridine 1b with piperidine 2 in the gas phase is reported using hybrid density functional theory method B3PW91 and 6-31G(d,p) basis set. The reaction was modeled via both the catalyzed and base-catalyzed pathways which proceeded with the initial attack of the nucleophile 2 on the substrates 1 to yield the Meisenheimer complex intermediate that is stabilized with hydrogen bonding. Calculations show that the reaction goes via the formation and decomposition of a Meisenheimer complex, which was observed to be stabilized by hydrogen bonding. Along the uncatalyzed pathway, the decomposition of the Meisenheimer complex was the slow step and requires about 28 kcal/mol. This barrier was reduced to about 14.8 kcal/mol with the intervention of the base catalyst, thus making the formation of the Meisenheimer complex rate determining. All reactions were calculated to be exothermic, about −6.5 kcal/mol and −0.6 kcal/mol, respectively, for the reaction of 1a and 1b with 2.
Abstract
A computational study of the chemical kinetics and thermodynamics study of the SNAr between 3,5-dinitroethoxypyridine 1a and 3,5-dinitromethoxypyridine 1b with piperidine 2 in the gas phase is reported using hybrid density functional theory method B3PW91 and 6-31G(d,p) basis set. The reaction was modeled via both the catalyzed and base-catalyzed pathways which proceeded with the initial attack of the nucleophile 2 on the substrates 1 to yield the Meisenheimer complex intermediate that is stabilized with hydrogen bonding. Calculations show that the reaction goes via the formation and decomposition of a Meisenheimer complex, which was observed to be stabilized by hydrogen bonding. Along the uncatalyzed pathway, the decomposition of the Meisenheimer complex was the slow step and requires about 28 kcal/mol. This barrier was reduced to about 14.8 kcal/mol with the intervention of the base catalyst, thus making the formation of the Meisenheimer complex rate determining. All reactions were calculated to be exothermic, about −6.5 kcal/mol and −0.6 kcal/mol, respectively, for the reaction of 1a and 1b with 2.
Kapitel in diesem Buch
- Frontmatter I
- Preface of the Book of Proceedings of the Virtual Conference on Computational Science (VCCS-2019) V
- Contents VII
- Corresponding authors XIII
- 1 Structural and spectroscopic properties of 3-halogenobenzaldehydes: DFT and TDDFT simulations 1
- 2 Atomistic insight into the significantly enhanced photovoltaic cells of monolayer GaTe2 via two-dimensional van der Waals heterostructures engineering 15
- 3 Fluorescent styryl chromophores with rigid (pyrazole) donor and rigid (benzothiophenedioxide) acceptor – complete density functional theory (DFT), TDDFT and nonlinear optical study 33
- 4 Comparative studies of excited state intramolecular proton transfer (ESIPT) and azohydrazone tautomerism in naphthalene-based fluorescent acid azo dyes by computational study 61
- 5 Theoretical examination of efficiency of anthocyanidins as sensitizers in dye-sensitized solar cells 83
- 6 Selection of oxypeucedanin as a potential antagonist from molecular docking analysis of HSP90 103
- 7 Mechanistic insight into the interactions between thiazolidinedione derivatives and PTP-1B combining 3D QSAR andmolecular docking in the treatment of type 2 diabetes 113
- 8 Review of research of nanocomposites based on graphene quantum dots 135
- 9 A computational study of the SNAr reaction of 2-ethoxy-3,5-dinitropyridine and 2-methoxy-3, 5-dinitropyridine with piperidine 161
- 10 Synthesis, characterization and computational studies of 1,3-bis[(E)-furan-2-yl)methylene]urea and 1,3-bis[(E)-furan-2-yl)methylene]thiourea 177
- 11 Computational studies of biologically active alkaloids of plant origin: an overview 187
- 12 Investigating the biological actions of some Schiff bases using density functional theory study 219
- 13 Molecular mechanics approaches for rational drug design: forcefields and solvation models 233
- Index 255
Kapitel in diesem Buch
- Frontmatter I
- Preface of the Book of Proceedings of the Virtual Conference on Computational Science (VCCS-2019) V
- Contents VII
- Corresponding authors XIII
- 1 Structural and spectroscopic properties of 3-halogenobenzaldehydes: DFT and TDDFT simulations 1
- 2 Atomistic insight into the significantly enhanced photovoltaic cells of monolayer GaTe2 via two-dimensional van der Waals heterostructures engineering 15
- 3 Fluorescent styryl chromophores with rigid (pyrazole) donor and rigid (benzothiophenedioxide) acceptor – complete density functional theory (DFT), TDDFT and nonlinear optical study 33
- 4 Comparative studies of excited state intramolecular proton transfer (ESIPT) and azohydrazone tautomerism in naphthalene-based fluorescent acid azo dyes by computational study 61
- 5 Theoretical examination of efficiency of anthocyanidins as sensitizers in dye-sensitized solar cells 83
- 6 Selection of oxypeucedanin as a potential antagonist from molecular docking analysis of HSP90 103
- 7 Mechanistic insight into the interactions between thiazolidinedione derivatives and PTP-1B combining 3D QSAR andmolecular docking in the treatment of type 2 diabetes 113
- 8 Review of research of nanocomposites based on graphene quantum dots 135
- 9 A computational study of the SNAr reaction of 2-ethoxy-3,5-dinitropyridine and 2-methoxy-3, 5-dinitropyridine with piperidine 161
- 10 Synthesis, characterization and computational studies of 1,3-bis[(E)-furan-2-yl)methylene]urea and 1,3-bis[(E)-furan-2-yl)methylene]thiourea 177
- 11 Computational studies of biologically active alkaloids of plant origin: an overview 187
- 12 Investigating the biological actions of some Schiff bases using density functional theory study 219
- 13 Molecular mechanics approaches for rational drug design: forcefields and solvation models 233
- Index 255
