DFI' calculations of O-H•••O 1H NMR chemical shifts in investigating enol-enol tautomeric equilibria: Probing the impacts of intramolecular hydrogen bonding vs stereoelectronic interactions

被引：9

作者：

Siskos, Michael G. ^{[1
]}

Varras, Panayiotis C. ^{[1
]}

Gerothanassis, Ioannis P. ^{[1
]}

机构：

[1] Univ Ioannina, Dept Chem, Sect Organ Chem & Biochem, GR-45110 Ioannina, Greece

来源：

TETRAHEDRON | 2020年 / 76卷 / 09期

关键词：

DFT; CPCM; Hydrogen bonding; H-1 NMR chemical shifts; Enol tautomers; AB-INITIO CALCULATIONS; COMPUTATIONAL NMR-SPECTROSCOPY; NUCLEAR-MAGNETIC-RESONANCE; SOLID-STATE NMR; C-13; NMR; NATURAL-PRODUCTS; PROTON-TRANSFER; GAS-PHASE; X-RAY; FORMS;

D O I：

10.1016/j.tet.2020.130979

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

An approach for investigating the impacts of hydrogen bonding and stereochemical interactions of enolenol tautomeric equilibria of beta-dicarbonyl compounds is presented. DFT quantum chemical calculations of O-H center dot center dot center dot O H-1 NMR chemical shifts of enol pairs, weighted by their proportions center dot as predicted by the relative free energies computed for them at the DFT level, agree well with experimental NMR chemical shifts. The main parameters affecting equilibrium constants for a set of eleven compounds, each one of which exists in two tautomeric forms in CHCl3 solution, are ring strain and steric repulsion of substituents with differences in O-H center dot center dot center dot O hydrogen bond lengths playing a secondary role. (C) 2020 Elsevier Ltd. All rights reserved.

引用

页数：8

共 67 条

[11]

Bolvig S, 1998, MAGN RESON CHEM, V36, P315, DOI 10.1002/(SICI)1097-458X(199805)36:5<315::AID-OMR251>3.0.CO

[12]

2-P

[13]

Bolvig S, 1996, MAGN RESON CHEM, V34, P467

[14] Variable-temperature NMR study of the enol forms of benzoylacetones [J].

Borisov, EV ;

Skorodumov, EV ;

Pachevskaya, VM ;

Hansen, PE .

MAGNETIC RESONANCE IN CHEMISTRY, 2005, 43 (12) :992-998

[15] KETO-ENOL-TAUTOMERISM IN 2-ACETYLTETRALONE - A REINVESTIGATION [J].

BORISOV, EV ;

AGRAWAL, PK .

MAGNETIC RESONANCE IN CHEMISTRY, 1994, 32 (08) :499-499

[16]

Borisov EV, 1998, MAGN RESON CHEM, V36, pS104, DOI 10.1002/(SICI)1097-458X(199806)36:13<S104::AID-OMR302>3.0.CO

[17]

2-G

[18] Accurate conformation analysis in solution:: NMR and DFT/PCM study of the S-3-(1-naphthoyl)-4-isopropyl-2,2-dimethyloxazolidin-5-one in CDCl3 [J].

Branca, Mathieu ;

Alezra, Valerie ;

Kouklovsky, Cyrille ;

Archirel, Pierre .

TETRAHEDRON, 2008, 64 (08) :1743-1752

[19] 1H-NMR as a Structural and Analytical Tool of Intra- and Intermolecular Hydrogen Bonds of Phenol-Containing Natural Products and Model Compounds [J].

Charisiadis, Pantelis ;

Kontogianni, Vassiliki G. ;

Tsiafoulis, Constantinos G. ;

Tzakos, Andreas G. ;

Siskos, Michael ;

Gerothanassis, Ioannis P. .

MOLECULES, 2014, 19 (09) :13643-13682

[20] A comparison of models for calculating nuclear magnetic resonance shielding tensors [J].

Cheeseman, JR ;

Trucks, GW ;

Keith, TA ;

Frisch, MJ .

JOURNAL OF CHEMICAL PHYSICS, 1996, 104 (14) :5497-5509

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