STERIC INHIBITION OF RESONANCE: IV. FURTHER SPECTROSCOPIC STUDIES OF 9-NITROANTHRACENE AND 9,10-DINITROANTHRACENE

The frequencies of the NO2 symmetrical stretching vibrations, and the ultraviolet absorption spectra, of solutions of 9-nitroanthracene and 9,10-dinitroanthracene have been measured and correlated with the deviations from coplanarity and resultant resonance inhibition.

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Spectroscopic Studies of Mixed Amine Carbonyl Complexes of d6Structure. I. Visible and Ultraviolet Absorption Spectra of Diamine-tetracarbonyl Complexes of Chromium(0), Molybdenum(0) and Tungsten(0)

Bulletin of the Chemical Society of Japan ◽

10.1246/bcsj.41.359 ◽

1968 ◽

Vol 41 (2) ◽

pp. 359-364 ◽

Cited By ~ 37

Author(s):

Hide Saito ◽

Junnosuke Fujita ◽

Kazuo Saito

Keyword(s):

Absorption Spectra ◽

Spectroscopic Studies ◽

Ultraviolet Absorption ◽

Carbonyl Complexes ◽

And Tungsten

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THE ULTRAVIOLET ABSORPTION SPECTRA OF SOME CARBOXY DERIVATIVES OF NAPHTHALENE

Canadian Journal of Research ◽

10.1139/cjr49b-047 ◽

1949 ◽

Vol 27b (5) ◽

pp. 437-461 ◽

Cited By ~ 22

Author(s):

Y. Hirshberg ◽

R. Norman Jones

Keyword(s):

Dicarboxylic Acid ◽

Absorption Spectra ◽

General Problem ◽

Acid Anhydride ◽

Ultraviolet Absorption ◽

Dioxane Solution ◽

Ethanolic Solution ◽

Complex Molecules ◽

Steric Inhibition Of Resonance ◽

Derivatives Of

The ultraviolet absorption spectra of a variety of naphthalene compounds containing phenyl and carboxy substituents are described. The majority of the compounds contain either the naphthalene-1,2-dicarboxylic acid anhydride or the naphthalene-2,3-dicarboxylic acid anhydride ring systems. It is shown that in ethanolic solution the spectra of these anhydrides change over a period of a few hours. The spectra of the anhydrides in n-heptane or dioxane solution do not change on standing. The effects of the various substituents are discussed in terms of steric inhibition of resonance and of antagonistic and reinforcing actions of the substituents, dependent on the position of substitution. The significance of these data are considered in relation to the general problem of the interpretation of the ultraviolet absorption spectra of complex molecules.

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SPECTROSCOPIC STUDIES OF KETO–ENOL EQUILIBRIA: PART 2. ANOMALOUS ULTRAVIOLET ABSORPTION SPECTRA OF SATURATED 1,2-DICYANO ESTERS

Canadian Journal of Chemistry ◽

10.1139/v62-352 ◽

1962 ◽

Vol 40 (12) ◽

pp. 2272-2277 ◽

Cited By ~ 10

Author(s):

T. R. Kasturi ◽

B. N. Mylari ◽

A. Balasubramanian ◽

C. N. R. Rao

Keyword(s):

Absorption Band ◽

Absorption Spectra ◽

Spectroscopic Studies ◽

Anomalous Behavior ◽

Enol Form ◽

Ultraviolet Absorption ◽

Polar Solvents ◽

Solvent Dependence

1,2-Dicyano esters show an absorption band around 245 mμ in alcoholic solutions which is not found in non-polar and other polar solvents. This anomalous behavior has been found to be due to the unusual solvent dependence of the equilibrium between the keto and enol forms. The intensity of the absorption band in alcoholic solutions decreases with increase in concentration of the 1,2-dicyano ester, indicating association of the enol form. The keto–enol equilibrium is also found to be sensitive to the substituent R of the alcohol ROH.

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