Molecular structure and intramolecular hydrogen bond strength of 3-methyl-4-amino-3-penten-2-one and its N-Me and N-Ph substitutions by experimental and theoretical methods

Seyedabdollah Seyedkatouli , Mohammad Vakili, Sayyed Faramarz Tayyari , Poul Erik Hansen, Fadhil S. Kamounah

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

Resumé

In the present work, molecular structures and intramolecular hydrogen bonding (IHB) of 3-methyl-4-amino-3-penten-2-one, 3-MeAPO, 3-methyl-4-methylamino-3-penten-2-one, 3-Me-MeAPO, and the 3-methyl-4-phenylamino-3-penten-2-one, 3-Me-PhAPO have been investigated by means of density functional theory (DFT) calculations, at the B3LYP/6-311++G** level, and experimental investigations including NMR, IR, Raman, UV spectroscopy, and X-ray crystallographic methods. The mentioned results were compared to those of 4-amino-3-penten-2-one, APO. DFT calculations suggest a relatively strong intramolecular hydrogen bond in 3-MeAPO and its N–Me and N-Ph substituted derivatives with N⋯O distances of 2.597, 2.584, and 2.581 Å, and calculated hydrogen bond energies of about 10.9, 13.6, and 14.9 kcal/mol in 3-MeAPO, 3-Me-MeAPO, and 3-Me-PhAPO, respectively. While, the calculated N⋯O distances and hydrogen bond energies, of APO, 2.669 Å and 7.67 kcal/mol respectively, suggest a medium IHB strength. According to the NBO results, the steric effect is the dominant factor for changes of the IHBs. The calculated geometrical parameters of 3-MeAPO are in excellent agreement with the X-ray results. UV-Vis spectra of 3-MeAPO, 3-Me-PhAPO, and 3-Me-MeAPO were recorded in ethanol supporting the results mentioned above. According to the calculated results and deuterium isotope effects on ¹³ C chemical shifts, 3-MeAPO exists as a keto-amine. Comparison of the observed and theoretical IR and Raman spectra and the spectral behavior upon deuteration were used for assignment of the vibrational spectra of 3-MeAPO. The assigned normal modes were compared to those of APO. The theoretical results were in good agreement with the experimental data. The vibrational frequencies also confirmed that the IHB strength in 3-MeAPO is stronger than that in APO.
OriginalsprogEngelsk
TidsskriftJournal of Molecular Structure
Vol/bind1184
Sider (fra-til)233-245
Antal sider13
ISSN0022-2860
DOI
StatusUdgivet - 11 feb. 2019

Emneord

  • isotope effects
  • Infra red sepctrosscopy
  • hydrogne bond energy

Citer dette

@article{55d836dd12fc419cb0abd5143be6d3db,
title = "Molecular structure and intramolecular hydrogen bond strength of 3-methyl-4-amino-3-penten-2-one and its N-Me and N-Ph substitutions by experimental and theoretical methods",
abstract = "In the present work, molecular structures and intramolecular hydrogen bonding (IHB) of 3-methyl-4-amino-3-penten-2-one, 3-MeAPO, 3-methyl-4-methylamino-3-penten-2-one, 3-Me-MeAPO, and the 3-methyl-4-phenylamino-3-penten-2-one, 3-Me-PhAPO have been investigated by means of density functional theory (DFT) calculations, at the B3LYP/6-311++G** level, and experimental investigations including NMR, IR, Raman, UV spectroscopy, and X-ray crystallographic methods. The mentioned results were compared to those of 4-amino-3-penten-2-one, APO. DFT calculations suggest a relatively strong intramolecular hydrogen bond in 3-MeAPO and its N–Me and N-Ph substituted derivatives with N⋯O distances of 2.597, 2.584, and 2.581 {\AA}, and calculated hydrogen bond energies of about 10.9, 13.6, and 14.9 kcal/mol in 3-MeAPO, 3-Me-MeAPO, and 3-Me-PhAPO, respectively. While, the calculated N⋯O distances and hydrogen bond energies, of APO, 2.669 {\AA} and 7.67 kcal/mol respectively, suggest a medium IHB strength. According to the NBO results, the steric effect is the dominant factor for changes of the IHBs. The calculated geometrical parameters of 3-MeAPO are in excellent agreement with the X-ray results. UV-Vis spectra of 3-MeAPO, 3-Me-PhAPO, and 3-Me-MeAPO were recorded in ethanol supporting the results mentioned above. According to the calculated results and deuterium isotope effects on ¹³ C chemical shifts, 3-MeAPO exists as a keto-amine. Comparison of the observed and theoretical IR and Raman spectra and the spectral behavior upon deuteration were used for assignment of the vibrational spectra of 3-MeAPO. The assigned normal modes were compared to those of APO. The theoretical results were in good agreement with the experimental data. The vibrational frequencies also confirmed that the IHB strength in 3-MeAPO is stronger than that in APO.",
keywords = "isotope effects, Infra red sepctrosscopy, hydrogne bond energy",
author = "Seyedabdollah Seyedkatouli and Mohammad Vakili and Tayyari, {Sayyed Faramarz} and Hansen, {Poul Erik} and Kamounah, {Fadhil S.}",
year = "2019",
month = "2",
day = "11",
doi = "10.1016/j.molstruc.2019.02.007",
language = "English",
volume = "1184",
pages = "233--245",
journal = "Journal of Molecular Structure",
issn = "0022-2860",
publisher = "Elsevier BV",

}

Molecular structure and intramolecular hydrogen bond strength of 3-methyl-4-amino-3-penten-2-one and its N-Me and N-Ph substitutions by experimental and theoretical methods. / Seyedkatouli , Seyedabdollah ; Vakili, Mohammad; Tayyari , Sayyed Faramarz ; Hansen, Poul Erik; Kamounah, Fadhil S.

I: Journal of Molecular Structure, Bind 1184, 11.02.2019, s. 233-245.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

TY - JOUR

T1 - Molecular structure and intramolecular hydrogen bond strength of 3-methyl-4-amino-3-penten-2-one and its N-Me and N-Ph substitutions by experimental and theoretical methods

AU - Seyedkatouli , Seyedabdollah

AU - Vakili, Mohammad

AU - Tayyari , Sayyed Faramarz

AU - Hansen, Poul Erik

AU - Kamounah, Fadhil S.

PY - 2019/2/11

Y1 - 2019/2/11

N2 - In the present work, molecular structures and intramolecular hydrogen bonding (IHB) of 3-methyl-4-amino-3-penten-2-one, 3-MeAPO, 3-methyl-4-methylamino-3-penten-2-one, 3-Me-MeAPO, and the 3-methyl-4-phenylamino-3-penten-2-one, 3-Me-PhAPO have been investigated by means of density functional theory (DFT) calculations, at the B3LYP/6-311++G** level, and experimental investigations including NMR, IR, Raman, UV spectroscopy, and X-ray crystallographic methods. The mentioned results were compared to those of 4-amino-3-penten-2-one, APO. DFT calculations suggest a relatively strong intramolecular hydrogen bond in 3-MeAPO and its N–Me and N-Ph substituted derivatives with N⋯O distances of 2.597, 2.584, and 2.581 Å, and calculated hydrogen bond energies of about 10.9, 13.6, and 14.9 kcal/mol in 3-MeAPO, 3-Me-MeAPO, and 3-Me-PhAPO, respectively. While, the calculated N⋯O distances and hydrogen bond energies, of APO, 2.669 Å and 7.67 kcal/mol respectively, suggest a medium IHB strength. According to the NBO results, the steric effect is the dominant factor for changes of the IHBs. The calculated geometrical parameters of 3-MeAPO are in excellent agreement with the X-ray results. UV-Vis spectra of 3-MeAPO, 3-Me-PhAPO, and 3-Me-MeAPO were recorded in ethanol supporting the results mentioned above. According to the calculated results and deuterium isotope effects on ¹³ C chemical shifts, 3-MeAPO exists as a keto-amine. Comparison of the observed and theoretical IR and Raman spectra and the spectral behavior upon deuteration were used for assignment of the vibrational spectra of 3-MeAPO. The assigned normal modes were compared to those of APO. The theoretical results were in good agreement with the experimental data. The vibrational frequencies also confirmed that the IHB strength in 3-MeAPO is stronger than that in APO.

AB - In the present work, molecular structures and intramolecular hydrogen bonding (IHB) of 3-methyl-4-amino-3-penten-2-one, 3-MeAPO, 3-methyl-4-methylamino-3-penten-2-one, 3-Me-MeAPO, and the 3-methyl-4-phenylamino-3-penten-2-one, 3-Me-PhAPO have been investigated by means of density functional theory (DFT) calculations, at the B3LYP/6-311++G** level, and experimental investigations including NMR, IR, Raman, UV spectroscopy, and X-ray crystallographic methods. The mentioned results were compared to those of 4-amino-3-penten-2-one, APO. DFT calculations suggest a relatively strong intramolecular hydrogen bond in 3-MeAPO and its N–Me and N-Ph substituted derivatives with N⋯O distances of 2.597, 2.584, and 2.581 Å, and calculated hydrogen bond energies of about 10.9, 13.6, and 14.9 kcal/mol in 3-MeAPO, 3-Me-MeAPO, and 3-Me-PhAPO, respectively. While, the calculated N⋯O distances and hydrogen bond energies, of APO, 2.669 Å and 7.67 kcal/mol respectively, suggest a medium IHB strength. According to the NBO results, the steric effect is the dominant factor for changes of the IHBs. The calculated geometrical parameters of 3-MeAPO are in excellent agreement with the X-ray results. UV-Vis spectra of 3-MeAPO, 3-Me-PhAPO, and 3-Me-MeAPO were recorded in ethanol supporting the results mentioned above. According to the calculated results and deuterium isotope effects on ¹³ C chemical shifts, 3-MeAPO exists as a keto-amine. Comparison of the observed and theoretical IR and Raman spectra and the spectral behavior upon deuteration were used for assignment of the vibrational spectra of 3-MeAPO. The assigned normal modes were compared to those of APO. The theoretical results were in good agreement with the experimental data. The vibrational frequencies also confirmed that the IHB strength in 3-MeAPO is stronger than that in APO.

KW - isotope effects

KW - Infra red sepctrosscopy

KW - hydrogne bond energy

U2 - 10.1016/j.molstruc.2019.02.007

DO - 10.1016/j.molstruc.2019.02.007

M3 - Journal article

VL - 1184

SP - 233

EP - 245

JO - Journal of Molecular Structure

JF - Journal of Molecular Structure

SN - 0022-2860

ER -