Reactions of nitrophenide and halonitrophenide ions with acrylonitrile and alkyl acrylates in the gas phase: addition to the carbonyl group versus Michael addition

2012 ◽  
Vol 47 (4) ◽  
pp. 425-438 ◽  
Author(s):  
Magdalena Zimnicka ◽  
Beata Wileńska ◽  
Osamu Sekiguchi ◽  
Einar Uggerud ◽  
Witold Danikiewicz
Keyword(s):  
Gas Phase ◽  
Carbonyl Group ◽  
Michael Addition ◽  
Group Versus ◽  
Alkyl Acrylates

ChemInform Abstract: The Nucleophilic Addition-Elimination Reaction on the Carbonyl Group of Pivaloyl Chloride, S-Methyl Thiopivaloate and 1-Pivaloyl-1,2,4-triazole in the Gas Phase.

ChemInform ◽  
1988 ◽  
Vol 19 (42) ◽  
Author(s):  
H. VAN DER WEL ◽  
G. J. M. BRUIN ◽  
S. J. J. VAN DER LINDE ◽  
N. M. M. NIBBERING ◽  
J. B. F. N. ENGBERTS
Keyword(s):  
Gas Phase ◽  
Carbonyl Group ◽  
Nucleophilic Addition ◽  
Elimination Reaction

The photoelectron spectra and electronic structure of 2-carbonyl furans

1990 ◽  
Vol 68 (5) ◽  
pp. 747-754 ◽  
Author(s):  
Dieter Klapstein ◽  
Charles D. MacPherson ◽  
Robert T. O'Brien
Keyword(s):  
Electronic Structure ◽  
Fine Structure ◽  
Gas Phase ◽  
Carbonyl Group ◽  
Ionization Energy ◽  
Furan Ring ◽  
Photoelectron Spectra ◽  
Energy Bands ◽  
Rotational Isomers ◽  
Inductive Effects

The He(I), λ = 58.4 nm, photoelectron spectra of a series of six 2-carbonyl furans and 2-furonitrile have been measured in the gas phase. The low ionization energy bands are assigned to photoionizations from π orbitals of the furan ring, orbitals localized on the carbonyl group, and orbitals of the carbonyl substituents. Changes in ionization energies within the series can be rationalized in terms of the relative conjugative and inductive effects of the substituents. Substituent inductive effects were found to be dominant. The relatively broad vibrational fine structure on the low IE bands of the carbonyl furans could result from the presence of rotational isomers of the species. Keywords: photoelectron spectra, 2-carbonyl furans, molecular orbitals.

AM1 calculational and experimental evidence that a β-nitroxyl group significantly enhances the thermodynamic and kinetic acidities of ketones

1994 ◽  
Vol 72 (11) ◽  
pp. 2348-2350 ◽  
Author(s):  
Nick Henry Werstiuk ◽  
Chandra Deo Roy
Keyword(s):  
Experimental Evidence ◽  
Gas Phase ◽  
Carbonyl Group ◽  
Rate Constants ◽  
Second Order ◽  
Nitroxyl Group ◽  
Order Rate ◽  
Kinetics Of

The kinetics of NaOD-catalysed H/D exchange of 3,3,5,5-tetramethylcyclohexanone (1), 1-hydroxy-4-oxo-2,2,6,6-tetrame-thylpiperidine (2), 4-oxo-2,2,6,6-tetramethylpiperidine-1-oxyl (3), 9-hydroxynorpseudopelletierine (4), and norpseudopelle-tierine-9-oxyl (5) have been studied in 60:40 dioxane–D2O(v/v) at 25.0 °C. The second-order rate constants are 9.20 × 10−3, 6.39 × 10−2, 1.59, 2.20 × 10−2, and 5.67 × 10−1 L mol−1 s−1 for 1, 2, 3, 4, and 5, respectively. Gas-phase enthalpies of ionization (the values are 363.0, 359.4, 352.0, 360.7, and 354.1 kcal mol−1 for 1, 2, 3, 4, and 5, respectively) calculated with AM1 correlate with the relative rates of enolization. Thus replacement of the β-hydroxylamino groups of 2 and 4 with a nitroxyl group produces sizable increases in the kinetic and thermodynamic acidities of the hydrogens α to the carbonyl group.

A molecular electron density theory (MEDT) study of the role of halogens (X2 = F2, Cl2, Br2 and I2) on the aza-Michael-addition reactions

2020 ◽  
Vol 44 (44) ◽  
pp. 19002-19012
Author(s):  
Luis R. Domingo ◽  
Ahmad Seif ◽  
Elham Mazarei ◽  
Ehasn Zahedi ◽  
Temer S. Ahmadi
Keyword(s):  
Gas Phase ◽  
Electron Density ◽  
Michael Addition ◽  
Nucleophilic Attack ◽  
Addition Reactions ◽  
Energy Profile ◽  
Molecular Electron ◽  
Molecular Electron Density Theory

The energy profile for gas phase F2-catalyzed nucleophilic attack of PYR R1 on the β-conjugated carbon of MA R2 marked.

The nucleophilic addition-elimination reaction on the carbonyl group of pivaloyl chloride, S-methyl thiopivaloate and 1-pivaloyl-1,2,4-triazole in the gas phase

2010 ◽  
Vol 107 (5) ◽  
pp. 370-380 ◽  
Author(s):  
H. van der Wel ◽  
G. J. M. Bruin ◽  
S. J. J. van der Linde ◽  
N. M. M. Nibbering ◽  
J. B. F. N. Engberts
Keyword(s):  
Gas Phase ◽  
Carbonyl Group ◽  
Nucleophilic Addition ◽  
Elimination Reaction

Backbone Carbonyl Group Basicities Are Related to Gas-Phase Fragmentation of Peptides and Protein Folding

2007 ◽  
Vol 46 (9) ◽  
pp. 1481-1484 ◽  
Author(s):  
Mikhail M. Savitski ◽  
Frank Kjeldsen ◽  
Michael L. Nielsen ◽  
Sergiy O. Garbuzynskiy ◽  
Oxana V. Galzitskaya ◽  
...  
Keyword(s):  
Protein Folding ◽  
Gas Phase ◽  
Carbonyl Group ◽  
Backbone Carbonyl ◽  
Gas Phase Fragmentation

Theoretical study of neighboring carbonyl group participation in the elimination kinetics of chloroketones in the gas phase

2010 ◽  
Vol 24 (3) ◽  
pp. 229-240 ◽  
Author(s):  
José R. Mora ◽  
Jesús Lezama ◽  
Edgar Márquez ◽  
Luz Escalante ◽  
Tania Córdova ◽  
...  
Keyword(s):  
Gas Phase ◽  
Carbonyl Group ◽  
Theoretical Study ◽  
Elimination Kinetics ◽  
Group Participation ◽  
Kinetics Of

ChemInform Abstract: THE ADDITION OF CARBANIONS TO THE CARBONYL GROUP IN THE GAS PHASE

1981 ◽  
Vol 12 (27) ◽  
Author(s):  
J. E. BARTMESS ◽  
R. L. HAYS ◽  
G. CALDWELL
Keyword(s):  
Gas Phase ◽  
Carbonyl Group
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