XCI.—Studies of dynamic isomerism. Part VIII. The relationship between absorption spectra and isomeric change. Absorption spectra of halogen, nitro-, and methyl derivatives of camphor

1909 ◽  
Vol 95 (0) ◽  
pp. 807-823 ◽  
Author(s):  
Thomas Martin Lowry ◽  
Cecil Henry Desch
Keyword(s):  
Absorption Spectra ◽  
Methyl Derivatives ◽  
The Relationship ◽  
Derivatives Of

Sulphonamides. II. Structure and Tautomerism of Sulphapyridine, Sulphathiazole, and Sulphanilylbenzamidine

1951 ◽  
Vol 4 (1) ◽  
pp. 93 ◽  
Author(s):  
SJ Angyal ◽  
WK Warburton
Keyword(s):  
Absorption Spectra ◽  
Structural Features ◽  
Ultraviolet Absorption ◽  
Amino Group ◽  
Dilute Solution ◽  
Methyl Derivatives ◽  
Derivatives Of

By the study of ultraviolet absorption spectra and comparison with methyl derivatives of known structure it is shown that the two forms of arylsulphonylbenzamidines described by Barber (1943) are tautomers, the more stable one having structure I. In dilute solution, sulphathiazole is found to be mainly X, and sulphapyridine a mixture of XIII and XIV in a ratio which depends on the solvent and can be influenced by changes on the p-amino group. Bands of the spectra are assigned to structural features of these molecules.

The infrared absorption spectra of thiosemicarbazide and related compounds: NH2 and NH vibrations

1969 ◽  
Vol 47 (6) ◽  
pp. 1087-1089 ◽  
Author(s):  
D. M. Wiles ◽  
T. Suprunchuk
Keyword(s):  
Absorption Spectra ◽  
Infrared Absorption ◽  
Significant Contribution ◽  
Methyl Derivatives ◽  
Infrared Absorption Spectra ◽  
Derivatives Of ◽  
Related Compounds

In the infrared absorption spectra of thiosemicarbazide (I), aldehyde thiosemicarbazones (II), and N-methyl derivatives of these compounds, the following assignments are proposed: νa(NdH2) absorbs in the vicinity of 3400 cm−1; NaH2 vibrations are observed in the region of 1630 cm−1; there is a significant contribution from ν(NbH) at or near 3170 cm−1. These conclusions probably apply to other thioamides and amides having related structures.

Physical Properties of TCNQ Salts with N-Methyl Derivatives of Pyridine

1982 ◽  
Vol 85 (1) ◽  
pp. 257-263 ◽  
Author(s):  
A. Graja ◽  
M. Przybylski ◽  
B. Butka ◽  
R. Swietlik
Keyword(s):  
Physical Properties ◽  
Methyl Derivatives ◽  
Derivatives Of

Methyl derivatives of furan

1974 ◽  
Vol 39 (11) ◽  
pp. 3109-3116 ◽  
Author(s):  
J. Šrogl ◽  
M. Janda ◽  
I. Stibor ◽  
V. Skála ◽  
P. Trška ◽  
...  
Keyword(s):  
Methyl Derivatives ◽  
Derivatives Of

Infrared spectra and substituent effects in 2-(3-, and 4-substituted phenylmethylene)-1,3-cycloheptanediones

1983 ◽  
Vol 48 (2) ◽  
pp. 586-595 ◽  
Author(s):  
Alexander Perjéssy ◽  
Pavol Hrnčiar ◽  
Ján Šraga
Keyword(s):  
Substituent Effects ◽  
Phenyl Group ◽  
Wave Number ◽  
Vibrational Coupling ◽  
Wave Numbers ◽  
Stretching Vibration ◽  
Stretching Vibrations ◽  
The Relationship ◽  
Derivatives Of ◽  
Effect Of Structure

The wave numbers of the fundamental C=O and C=C stretching vibrations, as well as that of the first overtone of C=O stretching vibration of 2-(3-, and 4-substituted phenylmethylene)-1,3-cycloheptanediones and 1,3-cycloheptanedione were measured in tetrachloromethane and chloroform. The spectral data were correlated with σ+ constants of substituents attached to phenyl group and with wave number shifts of the C=O stretching vibration of substituted acetophenones. The slope of the linear dependence ν vs ν+ of the C=C stretching vibration of the ethylenic group was found to be more than two times higher than that of the analogous correlation of the C=O stretching vibration. Positive values of anharmonicity for asymmetric C=O stretching vibration can be considered as an evidence of the vibrational coupling in a cyclic 1,3-dicarbonyl system similarly, as with derivatives of 1,3-indanedione. The relationship between the wave numbers of the symmetric and asymmetric C=O stretching vibrations indicates that the effect of structure upon both vibrations is symmetric. The vibrational coupling in 1,3-cycloheptanediones and the application of Seth-Paul-Van-Duyse equation is discussed in relation to analogous results obtained for other cyclic 1,3-dicarbonyl compounds.

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