Quinoxaline 1,4-dioxides. Substituent effects on the reaction of benzofurazan 1-oxides with carbonyl compounds

1975 ◽  
Vol 40 (2) ◽  
pp. 157-160 ◽  
Author(s):  
Elie Abushanab ◽  
Nicholas D. Alteri
Keyword(s):  
Carbonyl Compounds ◽  
Substituent Effects

scholarly journals Carbonyl Addition Reactions: Factors Affecting the Hydrate–Hemiacetal and Hemiacetal–Acetal Equilibrium Constants

1975 ◽  
Vol 53 (6) ◽  
pp. 898-906 ◽  
Author(s):  
J. Peter Guthrie
Keyword(s):  
Aqueous Solution ◽  
Carbonyl Compounds ◽  
Equilibrium Constants ◽  
Substituent Effects ◽  
Steric Effects ◽  
Addition Reactions ◽  
Free Energies ◽  
Electronic Effects ◽  
Factors Affecting ◽  
Analogous Formula

Equilibrium constants for hydrate–hemiacetal interconversion in aqueous solution at 25° have been measured for four fluorinated carbonyl compounds: compound, alcohol, K4 (M−1): CF3CHO, C2H5OH, 2.3; CF3COCH3, CH3OH, 1.0; CF3COPh, CH3OH, 3.5; CF3COCF3, CH3OH, 0.14. These values, combined with values from the literature, permit an examination of substituent effects upon the equilibrium constant for[Formula: see text]The free energy change for this process, corrected for symmetry and steric effects, follows the equation[Formula: see text]Thus electronic effects upon this equilibrium are generally small and in fact are often smaller than steric effects.This analysis permits and justifies the calculation of free energies of formation of [Formula: see text] compounds from the (more generally measurable) free energies of formation of the analogous [Formula: see text] compounds.

Gas phase basicities of fluorocarbonyl compounds. An ion cyclotron resonance investigation of the effects of fluorine and trifluoromethyl substituents on hydroxy carbonium ion stabilities

1981 ◽  
Vol 59 (18) ◽  
pp. 2689-2694 ◽  
Author(s):  
C. E. Doiron ◽  
T. B. McMahon
Keyword(s):  
Gas Phase ◽  
Carbonyl Compounds ◽  
Cyclotron Resonance ◽  
Substituent Effects ◽  
Ion Cyclotron Resonance ◽  
Proton Affinities ◽  
Resonance Investigation ◽  
Carbonium Ion ◽  
Hydrogen Bonding Interactions ◽  
Gas Phase Basicities

Gas phase proton affinities for a number of fluoro- and trifluoromethyl-substituted carbonyl compounds have been obtained using a combination of proton transfer equilibria and bracketing experiments. Absolute and relative substituent effects for F and CF3 on carbonyl basicities are determined and discussed in terms of inductive, resonance, polarization, and hydrogen bonding interactions. The data are used to interpolate basicities for HCOF and CF3CHO and are compared to theoretical ab initio calculations.

Reaction Profiles and Substituent Effects for the Reduction of Carbonyl Compounds with Monomer and Dimer Simple Metal Hydride Reagents

2005 ◽  
Vol 70 (13) ◽  
pp. 5157-5163 ◽  
Author(s):  
Takako Kudo ◽  
Takanori Higashide ◽  
Sachiyo Ikedate ◽  
Hiroshi Yamataka
Keyword(s):  
Metal Hydride ◽  
Carbonyl Compounds ◽  
Substituent Effects ◽  
Simple Metal
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