Author: A. G. Whittaker
Publisher:
ISBN:
Category :
Languages : en
Pages : 37
Book Description
The temperature dependence of the chemical shifts due to hindered internal rotation was measured for diethylformamide, diethylacetamide, diisopropylformamide, diisopropylacetamide and for solutions of these molecules in various solvents. In all cases, the chemical shifts showed unusual behavior. Conventional methods coupled with certain approximations were used to calculate activation energies as estimates for the rotational barrier to the internal rotation about the N-CO bond. These values were found to lie in the range of 5 to 26 kcal/mole. However, it is difficult to determine the real significance of these numbers; the behavior of the chemical shifts was such that no underlying concepts could be developed that would correlate the observed results except for the conclusion that the solvent plays a dominant role in the relationship between chemical shift and temperature. (Author).
Nuclear Magnetic Resonance Studies of Solvent Effects on the Hindered Internal Rotation in N, N-disubstituted Amides Higher Alkyl Amides
Author: A. G. Whittaker
Publisher:
ISBN:
Category :
Languages : en
Pages : 37
Book Description
The temperature dependence of the chemical shifts due to hindered internal rotation was measured for diethylformamide, diethylacetamide, diisopropylformamide, diisopropylacetamide and for solutions of these molecules in various solvents. In all cases, the chemical shifts showed unusual behavior. Conventional methods coupled with certain approximations were used to calculate activation energies as estimates for the rotational barrier to the internal rotation about the N-CO bond. These values were found to lie in the range of 5 to 26 kcal/mole. However, it is difficult to determine the real significance of these numbers; the behavior of the chemical shifts was such that no underlying concepts could be developed that would correlate the observed results except for the conclusion that the solvent plays a dominant role in the relationship between chemical shift and temperature. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 37
Book Description
The temperature dependence of the chemical shifts due to hindered internal rotation was measured for diethylformamide, diethylacetamide, diisopropylformamide, diisopropylacetamide and for solutions of these molecules in various solvents. In all cases, the chemical shifts showed unusual behavior. Conventional methods coupled with certain approximations were used to calculate activation energies as estimates for the rotational barrier to the internal rotation about the N-CO bond. These values were found to lie in the range of 5 to 26 kcal/mole. However, it is difficult to determine the real significance of these numbers; the behavior of the chemical shifts was such that no underlying concepts could be developed that would correlate the observed results except for the conclusion that the solvent plays a dominant role in the relationship between chemical shift and temperature. (Author).
Technical Abstract Bulletin
A Study of Molecular Structure and Internal Rotation in Amides by Nuclear Magnetic Resonance Spectroscopy
Author: Lester Reinhardt Isbrandt
Publisher:
ISBN:
Category : Amides
Languages : en
Pages : 292
Book Description
Publisher:
ISBN:
Category : Amides
Languages : en
Pages : 292
Book Description
Study of Hindered Internal Rotation in Some Substituted Amides by Nuclear Magnetic Resonance Spectroscopy
Author: James Calvin Woodbrey
Publisher:
ISBN:
Category : Amides
Languages : en
Pages : 420
Book Description
Publisher:
ISBN:
Category : Amides
Languages : en
Pages : 420
Book Description
A Nuclear Magnetic Resonance Study of Solvent Effects on the Thermodynamic Activition Parameters for Internal Rotation in N, N-Dimethyltrichloroacetamide
Author: Rosemary Ann Lowrey
Publisher:
ISBN:
Category : Amides
Languages : en
Pages : 88
Book Description
Publisher:
ISBN:
Category : Amides
Languages : en
Pages : 88
Book Description
International Aerospace Abstracts
Study of Hindered Internal Rotation in Some N-vinyl Substituted Amides by Nuclear Magnetic Resonance Spectroscopy
Author: Douglas George Gehring
Publisher:
ISBN:
Category : Amides
Languages : en
Pages : 94
Book Description
Publisher:
ISBN:
Category : Amides
Languages : en
Pages : 94
Book Description
Study of Hindered Internal Rotation in Some Substituted Amides by Nuclear Magnetic Resonance Spectroscopy
Author: William Chung-Tsing Tung
Publisher:
ISBN:
Category : Amides
Languages : en
Pages : 468
Book Description
Publisher:
ISBN:
Category : Amides
Languages : en
Pages : 468
Book Description
Proton Magnetic Resonance Spectroscopy Studies of the Substituted Aromatic Solvent Effect on the Hindered Internal Rotation of N,N-dimethylacetamide
Part I. Nuclear Magnetic Resonance Studies of Amides
Author: Biing-Ming Su
Publisher:
ISBN:
Category : Amides
Languages : en
Pages : 956
Book Description
Publisher:
ISBN:
Category : Amides
Languages : en
Pages : 956
Book Description