Gas-phase acidity of 1,1-bis(trifluoromethanesulfonyl) propane derivatives and related compounds: Experimental and theoretical studies

Min Zhang, Takaaki Sonoda, Yoshihito Shiota, Masaaki Mishima, Hikaru Yanai, Masaya Fujita, Takeo Taguchi

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The gas-phase acidity (GA) of a series of 1,1-bis(trifluoromethanesulfonyl)propane derivatives, Tf2CHCH2CH(R1)R2, and Tf2CHCH2Ar (Ar= phenol derivatives) was determined by measuring proton-transfer equilibria using a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer and by computing the free energy of the deprotonated carbanions and the corresponding neutrals. The effects of R1 and R2 or Ar groups on the acidity were examined. In Tf2CHCH2CH(R1)R2, the GA values calculated using the conformers of neutral molecules that are free from the intramolecular hydrogen-bonding interaction between the acidic hydrogen atom of the Tf2CH moiety and R1 or R2 group and between the hydrogen atom of the CHR1R2 moiety and the SO2CF3 group were correlated in terms of an equation, GA=-17.0∑σl + 3.4∑σα + 299.5. On the basis of this correlation, it was elucidated that the intramolecular hydrogen bonding or dipole-dipole interaction in the neutral molecule weakens significantly the acidity. In Tf2CHCH2Ar (5, 6, and 7), the GA was strengthened by the strong hydrogen-bonding interaction between the phenolic hydrogen in the aromatic moiety and the SO2CF3 group in the conjugate anion compared with that in the neutral molecule.

Original languageEnglish
Pages (from-to)181-186
Number of pages6
JournalJournal of Physical Organic Chemistry
Volume28
Issue number3
DOIs
Publication statusPublished - Jan 1 2015

Fingerprint

Propane
Acidity
acidity
propane
Gases
vapor phases
Derivatives
Hydrogen
Hydrogen bonds
hydrogen
Molecules
hydrogen atoms
dipoles
molecules
Cyclotron resonance
Atoms
Proton transfer
interactions
Mass spectrometers
cyclotron resonance

All Science Journal Classification (ASJC) codes

  • Physical and Theoretical Chemistry
  • Organic Chemistry

Cite this

Gas-phase acidity of 1,1-bis(trifluoromethanesulfonyl) propane derivatives and related compounds : Experimental and theoretical studies. / Zhang, Min; Sonoda, Takaaki; Shiota, Yoshihito; Mishima, Masaaki; Yanai, Hikaru; Fujita, Masaya; Taguchi, Takeo.

In: Journal of Physical Organic Chemistry, Vol. 28, No. 3, 01.01.2015, p. 181-186.

Research output: Contribution to journalArticle

Zhang, Min ; Sonoda, Takaaki ; Shiota, Yoshihito ; Mishima, Masaaki ; Yanai, Hikaru ; Fujita, Masaya ; Taguchi, Takeo. / Gas-phase acidity of 1,1-bis(trifluoromethanesulfonyl) propane derivatives and related compounds : Experimental and theoretical studies. In: Journal of Physical Organic Chemistry. 2015 ; Vol. 28, No. 3. pp. 181-186.
@article{2dd0268be5784b059709c686799e2d42,
title = "Gas-phase acidity of 1,1-bis(trifluoromethanesulfonyl) propane derivatives and related compounds: Experimental and theoretical studies",
abstract = "The gas-phase acidity (GA) of a series of 1,1-bis(trifluoromethanesulfonyl)propane derivatives, Tf2CHCH2CH(R1)R2, and Tf2CHCH2Ar (Ar= phenol derivatives) was determined by measuring proton-transfer equilibria using a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer and by computing the free energy of the deprotonated carbanions and the corresponding neutrals. The effects of R1 and R2 or Ar groups on the acidity were examined. In Tf2CHCH2CH(R1)R2, the GA values calculated using the conformers of neutral molecules that are free from the intramolecular hydrogen-bonding interaction between the acidic hydrogen atom of the Tf2CH moiety and R1 or R2 group and between the hydrogen atom of the CHR1R2 moiety and the SO2CF3 group were correlated in terms of an equation, GA=-17.0∑σl + 3.4∑σα + 299.5. On the basis of this correlation, it was elucidated that the intramolecular hydrogen bonding or dipole-dipole interaction in the neutral molecule weakens significantly the acidity. In Tf2CHCH2Ar (5, 6, and 7), the GA was strengthened by the strong hydrogen-bonding interaction between the phenolic hydrogen in the aromatic moiety and the SO2CF3 group in the conjugate anion compared with that in the neutral molecule.",
author = "Min Zhang and Takaaki Sonoda and Yoshihito Shiota and Masaaki Mishima and Hikaru Yanai and Masaya Fujita and Takeo Taguchi",
year = "2015",
month = "1",
day = "1",
doi = "10.1002/poc.3304",
language = "English",
volume = "28",
pages = "181--186",
journal = "Journal of Physical Organic Chemistry",
issn = "0894-3230",
publisher = "John Wiley and Sons Ltd",
number = "3",

}

TY - JOUR

T1 - Gas-phase acidity of 1,1-bis(trifluoromethanesulfonyl) propane derivatives and related compounds

T2 - Experimental and theoretical studies

AU - Zhang, Min

AU - Sonoda, Takaaki

AU - Shiota, Yoshihito

AU - Mishima, Masaaki

AU - Yanai, Hikaru

AU - Fujita, Masaya

AU - Taguchi, Takeo

PY - 2015/1/1

Y1 - 2015/1/1

N2 - The gas-phase acidity (GA) of a series of 1,1-bis(trifluoromethanesulfonyl)propane derivatives, Tf2CHCH2CH(R1)R2, and Tf2CHCH2Ar (Ar= phenol derivatives) was determined by measuring proton-transfer equilibria using a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer and by computing the free energy of the deprotonated carbanions and the corresponding neutrals. The effects of R1 and R2 or Ar groups on the acidity were examined. In Tf2CHCH2CH(R1)R2, the GA values calculated using the conformers of neutral molecules that are free from the intramolecular hydrogen-bonding interaction between the acidic hydrogen atom of the Tf2CH moiety and R1 or R2 group and between the hydrogen atom of the CHR1R2 moiety and the SO2CF3 group were correlated in terms of an equation, GA=-17.0∑σl + 3.4∑σα + 299.5. On the basis of this correlation, it was elucidated that the intramolecular hydrogen bonding or dipole-dipole interaction in the neutral molecule weakens significantly the acidity. In Tf2CHCH2Ar (5, 6, and 7), the GA was strengthened by the strong hydrogen-bonding interaction between the phenolic hydrogen in the aromatic moiety and the SO2CF3 group in the conjugate anion compared with that in the neutral molecule.

AB - The gas-phase acidity (GA) of a series of 1,1-bis(trifluoromethanesulfonyl)propane derivatives, Tf2CHCH2CH(R1)R2, and Tf2CHCH2Ar (Ar= phenol derivatives) was determined by measuring proton-transfer equilibria using a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer and by computing the free energy of the deprotonated carbanions and the corresponding neutrals. The effects of R1 and R2 or Ar groups on the acidity were examined. In Tf2CHCH2CH(R1)R2, the GA values calculated using the conformers of neutral molecules that are free from the intramolecular hydrogen-bonding interaction between the acidic hydrogen atom of the Tf2CH moiety and R1 or R2 group and between the hydrogen atom of the CHR1R2 moiety and the SO2CF3 group were correlated in terms of an equation, GA=-17.0∑σl + 3.4∑σα + 299.5. On the basis of this correlation, it was elucidated that the intramolecular hydrogen bonding or dipole-dipole interaction in the neutral molecule weakens significantly the acidity. In Tf2CHCH2Ar (5, 6, and 7), the GA was strengthened by the strong hydrogen-bonding interaction between the phenolic hydrogen in the aromatic moiety and the SO2CF3 group in the conjugate anion compared with that in the neutral molecule.

UR - http://www.scopus.com/inward/record.url?scp=85027951445&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85027951445&partnerID=8YFLogxK

U2 - 10.1002/poc.3304

DO - 10.1002/poc.3304

M3 - Article

AN - SCOPUS:85027951445

VL - 28

SP - 181

EP - 186

JO - Journal of Physical Organic Chemistry

JF - Journal of Physical Organic Chemistry

SN - 0894-3230

IS - 3

ER -