Amine Catalytic Reaction Of Nitro Alkanes And Aromatic Aldehydes Preparation Of Nitro Olefins

Nitro-olefins are very useful organic synthetic intermediates. They can be used in Michael addition, Diels-Alder reaction and polymerization. They also can be reduced to amines, hydrolyzed to carbonyl compounds and used in the synthesis of insecticides, fungicides and some other physiologically active substances. Many oxime compounds have excellent insecticidal, fungicidal, herbicidal activity and anti-viral activity of plants.Two types of reactions of carbonyl compounds with nitroalkanes by using amines as catalyst or reducing agent have been incestigated. The first reaction is amine-catalyzed formation of nitroalkenes via condensation between nitroalkanes and aldehydes. Ethylenediamine was found to be the best catalyst for the condensation, and low catalyst loading was found to be crucial for highly efficient synthesis of nitroalkenes. Various nitroalkenes can be synthesized in high yields via condensation of aromatic aldehydes and nitroalkanes with 1%-4%(mol) catalyst loading of ethylenediamine. The second reaction is the formation of ketoximes via reaction of ketones with excessive primary amines. Various ketoximes can be obtained in high yields from reaction of ketones with 2 molar equivalent of ethylenediamine at reflux in nitromethane or nitroethane.In this paper, it is found for the first time that the reaction between ketones and nitroalkanes produced the oximes, and that nitroalkenes can be obtained in high yields for the reaction of nitroalkanes with aromatic aldehydes by using the lowest catalyst loading (up to 0.01 equiv) of ethylenediamine.