Nuclear magnetic resonance studies of aziridines. Solvent effect, anisotropy effect of the nitrogen atom, and its variation with hydrogen bond formation

1967 ◽  
Vol 89 (25) ◽  
pp. 6605-6611 ◽  
Author(s):  
Hazime. Saito ◽  
Kenkichi. Nukada ◽  
Tsuneo. Kobayashi ◽  
Kenichi. Morita
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Hydrogen Bond ◽  
Magnetic Resonance ◽  
Nitrogen Atom ◽  
Solvent Effect ◽  
Bond Formation ◽  
Hydrogen Bond Formation ◽  
Magnetic Resonance Studies ◽  
Anisotropy Effect ◽  
Nuclear Magnetic

A nuclear magnetic resonance study of hydrogen bonding of δ-valerolactam

1969 ◽  
Vol 47 (19) ◽  
pp. 3655-3660 ◽  
Author(s):  
J. M. Purcell ◽  
H. Susi ◽  
J. R. Cavanaugh
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Magnetic Resonance ◽  
Chemical Shifts ◽  
Bond Formation ◽  
Resonance Spectroscopy ◽  
Hydrogen Bond Formation ◽  
Wide Range ◽  
Nuclear Magnetic

The association of amide groups of δ-valerolactam through hydrogen bonding has been investigated by means of high resolution nuclear magnetic resonance spectroscopy in CCl4 and CDCl3 solutions. Chemical shifts of the NH proton signal were measured over a wide range of temperatures and concentrations. Thermodynamic properties associated with the [Formula: see text] hydrogen bond formation were evaluated from a least squares analysis by a direct search procedure with a digital computer. The obtained enthalpy values for hydrogen bond formation are in general agreement with results obtained by other methods.

Nematic phase nuclear magnetic resonance studies of the structure and orientation of 1,5- and 2,6-naphthyridines

1976 ◽  
Vol 54 (17) ◽  
pp. 2783-2787 ◽  
Author(s):  
Y. P. Lee ◽  
D. F. R. Gilson
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Hydrogen Bond ◽  
Liquid Crystal ◽  
Magnetic Resonance ◽  
Nitrogen Atom ◽  
Nematic Phase ◽  
Proton Magnetic Resonance ◽  
Magnetic Resonance Studies ◽  
Molecular Dimension ◽  
Skeleton Structure

The proton magnetic resonance spectra of 1,5- and 2,6-naphthyridine dissolved in the nematic liquid crystal MBBA have been analysed. The proton geometries do not give good fits to the ring skeleton structure but it appears that the carbon–hydrogen bond lengths are not all of equal length and the bond angles indicate some bending of the C—H bonds toward the adjacent nitrogen atom. The probability functions for orientation of diazanaphthalenes in nematic solvents show that nitrogen atoms in the ring framework affect the direction of principal orientation, which does not follow either the maximum molecular dimension or the inertial axis.

Study of base hydrogen bond in N,2,6-trichloro-p-benzoquinone imine with nuclear magnetic resonance and infrared spectroscopy. The assignment of syn and anti proton signals in the chloroimino group

1968 ◽  
Vol 46 (19) ◽  
pp. 2989-3000 ◽  
Author(s):  
Hazime Saitô ◽  
Kenkichi Nukada
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Hydrogen Bond ◽  
Magnetic Resonance ◽  
Benzene Molecule ◽  
Wave Number ◽  
Benzoquinone Imine ◽  
Downfield Shift ◽  
Anisotropy Effect ◽  
Text Base ◽  
Nuclear Magnetic

The nuclear magnetic resonance (n.m.r.) spectra of N,2,6-trichloro-p-benzoquinone imine (1) and the anisotropy effect of the chloroimino group are investigated. A comparison of the n.m.r. spectra of 1 with those of oximes with a similar structure shows that the extent of the anisotropy effect is the same for both the chloroimino and the hydroxyimino group. This is also confirmed by comparison of N-chlorocyclohexanimine with cyclohexanone oxime. A downfield shift of the C—H proton signal in solvents acting as a base is observed, which is interpreted in terms of a [Formula: see text] base hydrogen bond. The extent of the shift is different between syn and anti sides and this gives the definite assignment for these two types of proton signals. Namely, the high-field signal, the extent of the downfield shift being larger, is assigned to anti protons, and the low-field one to syn protons. This assignment is extended to oximes owing to the equality of the anisotropy effects of the hydroxyimino and the chloroimino group. The formation of the [Formula: see text] base hydrogen bond is confirmed by the infrared (i.r.) spectra, and the correlation between the extents of n.m.r. downfield shift and i.r. low wave number shift is discussed. Furthermore it is found that the behavior of benzene molecule as solvent is different between the chloroimino and the hydroxyimino compounds.

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