29418-27-7Relevant academic research and scientific papers
The 4.4′-benzidine rearrangement of 4-alkyl substituted hydrazobenzenes
Bouillon, Marc E.,Meyer, Hartmut H.
supporting information, p. 3151 - 3161 (2016/05/24)
When treated with dilute inorganic acids N,N′-diarylhydrazines (hydrazobenzenes) with an alkyl substituent in the 4-position undergo [5,5]-sigmatropic rearrangement reactions to furnish 4-(4′-aminophenyl)-4-alkylcyclohexa-2,5-dienimines (ipso-benzidines) in moderate to excellent yields. Steric bulk of the 4-alkyl substituent in the starting material decreases the yield of the respective ipso-benzidine. Additional electron-donating alkyl substituents in the ortho- and/or meta-positions on both rings generally promote the reaction and consequently increase the yield of the 4.4′-benzidine rearrangement product. Described herein are our findings regarding the scope and limits of this unusual benzidine rearrangement.
Liquid Crystalline Solvents as Mechanistic Probes. 11. The Syn -> Anti Thermal Isomerization Mechanism of Some Low-"Bipolarity" Azobenzenes
Otruba, Joseph P.,Weiss, Richard G.
, p. 3448 - 3453 (2007/10/02)
The effects of solvent order on the syn -> anti isomerization rates of 15 azobenzenes have been investigated.The activation parameters determined in a cholesteric phase consisting of a 35/65 (w/w) mixture of cholesteryl chloride/cholesteryl nonanoate and in several other solvents are more consistent with an isomerization mechanism which proceeds via inversion (in plane) rather than rotation (out of plane).A correction of our previously reported data is given.The anomalous behavior of the isomerization mechanism of di-ortho-methylated azobenzenes is demonstrated by means of isokinetic plots.
