440. Aromatic azo-compounds. Part I. Oxidation of cis- and trans-azobenzene

1953 ◽  
pp. 2143 ◽  
Author(s):  
G. M. Badger ◽  
R. G. Buttery ◽  
G. E. Lewis
Keyword(s):  
Azo Compounds ◽  
Aromatic Azo Compounds ◽  
Cis And Trans ◽  
Trans Azobenzene

Radiation Induced cis and trans Isomerization of Polyisoprenes and Temperature Dependence of the Equilibria

1967 ◽  
Vol 40 (4) ◽  
pp. 1222-1229
Author(s):  
Jitsuo Tsurugi ◽  
Tsugio Fukumoto ◽  
Masayuki Yamagami ◽  
Hiroshi Itatani
Keyword(s):  
Transition State ◽  
Infrared Absorption ◽  
Rate Constants ◽  
Equilibrium Constants ◽  
Azo Compounds ◽  
Γ Radiation ◽  
Gutta Percha ◽  
Radiation Induced ◽  
Aromatic Azo Compounds ◽  
Cis And Trans

Abstract The cis and trans interconversion of polyisoprenes in solutions induced by γ-radiation in the presence of a sensitizer, which is any one of organic bromides or n-butyl mercaptan, was studied by using hevea and gutta percha as starting substances. The percentage cis remaining or converted after irradiation was determined by the infrared absorption. The equilibrium constants for the interconversion at 22, 60, and 100° C were found to be 3.00, 5.25, and 7.33, respectively. The firstorder rate constants for as cis → trans and trans → cis isomerizations at 22° C were calculated to be 9.05 and 2.91, respectively. The results were interpreted by the mechanism proposed by Golub, according to which the double bonds from π complexes with radiolytic fragments from sensitizers give a radical transition state capable of interconversion. However, our results showing that heating shifts the equilibrium toward trans isomer are not in accord with the mechanisms of the radiation-induced isomerization of polybutadiene of Golub and those for photoisom-erization of aromatic azo compounds.

Bifunctional Au/Co3O4‐Cs (Basic and Redox)‐ Catalyzed Oxidative Synthesis of Aromatic Azo Compounds from Anilines

2021 ◽  
Author(s):  
Charles O. Oseghale ◽  
Dele Peter Fapojuwo ◽  
Oyekunle Azeez Alimi ◽  
Christianah Aarinola Akinnawo ◽  
Batsile M. Mogudi ◽  
...  
Keyword(s):  
Azo Compounds ◽  
Aromatic Azo Compounds

Gold-Catalyzed Synthesis of Aromatic Azo Compounds from Anilines and Nitroaromatics

Science ◽  
2008 ◽  
Vol 322 (5908) ◽  
pp. 1661-1664 ◽  
Author(s):  
A. Grirrane ◽  
A. Corma ◽  
H. Garcia
Keyword(s):  
Azo Compounds ◽  
Aromatic Azo Compounds

ChemInform Abstract: THE REDUCTIVE HALOGENATION OF AROMATIC AZO COMPOUNDS

1975 ◽  
Vol 6 (51) ◽  
pp. no-no
Author(s):  
BRYCE D. WILKINSON ◽  
DUNCAN A. R. HAPPER
Keyword(s):  
Azo Compounds ◽  
Aromatic Azo Compounds

Massenspektrometrische Untersuchungen an Borchelaten, V [1] Fragmentierung borhaltiger aromatischer Azoverbindungen / Mass Spectrometric Investigation of Boron Chelates, V [1]Fragmentation of Aromatic Azo Compounds Containing Boron

1980 ◽  
Vol 35 (3) ◽  
pp. 316-318 ◽  
Author(s):  
Eberhard Hohaus ◽  
Wolfgang Riepe ◽  
Klaus Wessendorf
Keyword(s):  
Chelate Ring ◽  
Mass Spectrometric ◽  
Azo Compounds ◽  
Spectrometric Investigation ◽  
Mass Spectrometric Investigation ◽  
Boron Chelates ◽  
Molecular Ion ◽  
Significant Change ◽  
Structural Formulae ◽  
Aromatic Azo Compounds

Differing fragmentation of boron chelates of aromatic azo compounds confirms the structural formulae 1a-7c, presented in [2].More significant differences are caused by the substituent of the boron R (F instead of C6H5).Although certain rules can be deduced by the substitution of F for CeHs with regard to the change in intensity of the ions M+, M+-R (and others), in some cases the stable aromatic azo system causes a significant change in the fragmentation as compared with that of azomethine chelates. The chelates 7 eliminate “RH” and show no molecular ion. Apparently a second chelate ring is closed before further fragmentation can start. Fragmentation of 7 a and b is analogous to 5.

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