- Reduction of Aromatic Nitro Compounds by Ethylenediamine. A New Selective Reagent for the Synthesis of Symmetric Azo Compounds
-
Ethylenediamine selectively reduces aromatic nitro compounds RC6H4NO2 (R = H, m-CH3, p-CH3, and m-Ph) at 150 deg C to symmetric azo compounds RC6H4N=NC6H4R in good yield but does not reduce their ortho-substituted analogues.The diamine does not react with o- or p-nitroanilines but reduces the meta isomer to 1,3-diaminobenzene and 3,3'-diaminoazobenzene.Its reaction with o- and p-halonitrobenzenes gives substitution products H2NCH2CH2NHC6H4NO2.Nitrosobenzene is reduced to aniline and azobenzene, while α-nitroso-β-naphthol is converted to 1,4-phenanthroline.Among a variety of other amines tested, only 1,3-propylenediamine reduces nitrobenzene to azobenzene.A mechanism for the reaction is proposed.
- Chung, T. F.,Wu, Y. M.,Cheng, C. H.
-
p. 1215 - 1217
(2007/10/02)
-
- Insecticide evaporator comprising a stabilizer
-
Insecticide evaporator comprising at least one volatile phosphoric ester insecticide, an agent for stabilizing the said ester against decomposition by protonization and used in an amount of 0.2 to 20% based on the weight of phosphoric ester, characterized in that the stabilizing agent contains at least one compound selected from the compounds of the chemical class of 1,3-benzodioxoles and at least one diazene.
- -
-
-
- Evaporator system comprising a stabilized pesticidal phosphoric acid ester and method for stabilizing such ester enclosed in an evaporator
-
An evaporator system adapted for emitting insect killing vapors of an insecticide therefrom and comprising a liquid or solid composition enclosed therein, said insecticide consisting in at least one volatile phosphoric acid ester which is stabilized by at least one diazene compound.
- -
-
-