Aliphatic α-nitroalkyl-ONN-azoxy compounds and their derivatives

Abstract

Interaction of primary amines and 2,2 dimethyl 5 nitro 5 nitroso 1,3 dioxane in the pres ence of dibromoisocyanurate generates 2,2 dimethyl 5 nitro 1,3 dioxan 5 yl ONN azoxy alkanes. Based on the reaction of the latter with AcCl/MeOH followed by further transforma tions, the first representatives of mononitro and polynitroalkyl ONN azoxyalkanes, i.e., (meth yl NNO azoxy)nitromethane and dinitro(methyl NNO azoxy)methane, as well as some their derivatives, were prepared.Earlier it was shown that aryl NNO azoxy α nitro and polynitroalkanes 1,2 are quite thermally stable surpass ing in this aspect the isomeric aryl ONN azoxy α poly nitroalkanes. 3 In the present work the first members of a series of α nitro and α polynitroalkyl ONN azoxyal kanes and some of their derivatives were studied. These compounds may prove potentially valuable as rather ef fective energetic materials provided a favorable combina tion of composition and properties. In the literature there were described two nitroalkyl ONN azoxyalkanes, both obtained by reacting isopropyl pseudonitrole with the pri mary aliphatic amines (or their hydrochlorides) in the pres ence of dibromoisocyanurate (DBI). 4 Our study was based on the same approach. However, having neither indica tions for the existence of methylpseudonitrol nor any data implying its stability (taking into account the ability of aliphatic nitroso compounds carrying R 2 CHNO moi ety to isomerize readily into the corresponding oximes R 2 CNOH), we employed 2,2 dimethyl 5 nitro 5 nitroso 1,3 dioxane (1) as a formal source of methylpseudonitrol with "protected" α protons.The compound 1 was found to react smoothly with the primary amines (methylamine or tert butylamine) in methyl ene chloride at room temperature in the presence of DBI to form the corresponding (2,2 dimethyl 5 nitro 1,3 dioxan 5 yl) ONN azoxyalkanes 2 in 65-95% yields (Scheme 1).For this reaction the hydrochlorides of primary amines can be used instead of free amines, as well as N,N di bromoamines would suit instead of the combination of primary amine and DBI. Scheme 1 R = Me (a), Bu t (b)

First Synthesis of Aliphatic Nitro‐NNO‐azoxy Compounds

“…All other reagents were used without further purification. 2‐{[Dibromo(nitro)methyl]‐ ONN ‐azoxy}‐2‐methylpropane ( 5 ), bis( tert ‐butyl‐ NNO ‐azoxy)methane ( 7 ), 2‐nitro‐2‐nitrosopropane ( 8 ), were prepared according to the reported procedures.…”