119613-00-2Relevant academic research and scientific papers
Aryliminodimagnesium Reagents. XIV. Reactions with Nitrobenzenes Having Electronegative ortho-Substituents. Effects of Reaction Conditions on Condensation, Replacement, and Substitution
Okubo, Masao,Inatomi, Yoshito,Taniguchi, Naoki,Imamura, Kaori
, p. 3581 - 3586 (2007/10/02)
In reactions of ArN(MgBr)2 with o-MeO- and o-halo-substituted nitrobenzenes, types and yields of products were different from those in its reactions with m- and p-substituted substrates.Condensation (leading to unsymmetrical azoxy- and azobenzenes), o-substituent replacement, and nuclear substitution took place.Relative yields of products were greatly affected by substituents and reaction conditions. o-MeO and o-F favor replacement, while o-Cl, o-Br, and o-I favor substitution.Replacement and/or substitution predominate when small molar excess of reagent and low concentration are used, while condensation predominates when large molar excess of reagent and high concentration are used, which phenomenon is mechanistically discussed.
Facile Photorearrangement of Some Crowded Azoxyarenes via Two Concurrent Pathways
Okubo, Masao,Hyakutake, Hayato,Taniguchi, Naoki
, p. 3005 - 3007 (2007/10/02)
Naphthalene-1-ONN-azoxybenzenes and some unsymmetrically ortho-substituted ONN- and NNO-azoxybenzenes were prepared, and their photochemical behavior in ethanol was compared.The crowded azoxyarenes tend to undergo a facile Wallach rearrangement via the known azoxy-ortho oxygen migration and a concurrent pathway involving ONN-NNO-isomerization.The relative contribution of the two pathways was affected by substituents.
