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Molecular structure and electron distribution of 4-nitropyridine N-oxide: Experimental and theoretical study of substituent effects.

ABSTRACT: The molecular structure of 4-nitropyridine N-oxide, 4-NO2-PyO, has been determined by gas-phase electron diffraction monitored by mass spectrometry (GED/MS) and by quantum chemical calculations (DFT and MP2). Comparison of these results with those for non-substituted pyridine N-oxide and 4-methylpyridine N-oxide CH3-PyO, demonstrate strong substitution effects on structural parameters and electron density distribution. The presence of the electron-withdrawing -NO2 group in para-position of 4-NO2-PyO results in an increase of the ipso-angle and a decrease of the semipolar bond length r(N?O) in comparison to the non-substituted PyO. The presence of the electron-donating -CH3 group in 4-CH3-PyO leads to opposite structural changes. Electron density distribution in pyridine-N-oxide and its two substituted compounds are discussed in terms of natural bond orbitals (NBO) and quantum theory atoms in molecule (QTAIM).

SUBMITTER: Belova NV

PROVIDER: S-EPMC7230146 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Molecular structure and electron distribution of 4-nitropyridine N-oxide: Experimental and theoretical study of substituent effects.

Belova Natalya V NV Pimenov Oleg A OA Kotova Vitaliya E VE Girichev Georgiy V GV

Journal of molecular structure 20200517

The molecular structure of 4-nitropyridine N-oxide, 4-NO2-PyO, has been determined by gas-phase electron diffraction monitored by mass spectrometry (GED/MS) and by quantum chemical calculations (DFT and MP2). Comparison of these results with those for non-substituted pyridine N-oxide and 4-methylpyridine N-oxide CH3-PyO, demonstrate strong substitution effects on structural parameters and electron density distribution. The presence of the electron-withdrawing -NO2</sub ...[more]

PMID: 32427177

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Dataset Information

Molecular structure and electron distribution of 4-nitropyridine N-oxide: Experimental and theoretical study of substituent effects.

Publications

Molecular structure and electron distribution of 4-nitropyridine N-oxide: Experimental and theoretical study of substituent effects.

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