High energy and moderate sensitivity are the two most important demands for modern energetic materials. The powerful CL-20 and its previously obtained analogs do not meet safety requirements. To reach...

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Reaction of secondary amines with the nitrite anion assisted by diacetoxyiodobenzene results in respective N nitroamines. It is the first example of oxidative nitration of the amino group. N Nitrosoamines are by products. The yields and the ratio of the nitration and nitrosa tion products depend on the nature of the starting amine, cation of the salt used, and the solvent.Reactions where the nitrite anion is a source of a cova lent nitro group are scarce. One of them is the oxidative nitration of primary and secondary C nitro compounds with the nitrite anion to gem dinitro compounds using Ag + or Fe +3 ions as oxidants. 1,2 The putative reaction mechanism involves the formation of intermediate A (Scheme 1). 2 Scheme 1The oxidant is a crucial reactant in the oxidative nitra tion. Compounds of hypervalent iodine have been widely used in organic synthesis as reactive and convenient oxi dizing agents over the last 25-30 years. 3,4 Combinations of aryliodo(III) derivatives (λ 3 iodanes) with such salts as NaN 3 5 or LiBr 6 resulting in oxidative functionalization of a CH bond were described in literature, but analogous combination λ 3 iodane/NaNO 2 has not been used as a nitrating reagent. Apparently, no example of the oxida tive nitration of the NH bond have been described so far.We demonstrated a possibility of nitration of the ami no group with nitrite salts and diacetoxyiodobenzene for the first time. The reaction occurs under neutral condi tions.It was shown that the reaction of secondary amines 1a-e with the nitrite anion in the presence of PhI(OAc) 2 (2), according to 1 H NMR data, gives the corresponding N nitroamines 3 in a yield of up to 40%, ~20-30% of N nitrosoamines 4 being also formed (Scheme 2). Scheme 2 R = Et (a), PhCH 2 (b), MeO 2 CCH 2 CH 2 (c), NCCH 2 CH 2 (d); R 2 N is morpholino (e); M = Na, K, Li, Et 4 N, Ag.The effect of the solvent, the nitrite salt cation, and the temperature regime of the reaction were studied by the example of bis(2 cyanoethyl)amine 1d. The choice of sol vents is interrelated with the choice of cations since apro tic solvents require salts with the appropriate solubility. By the example of [Et 4 N]NO 2 and LiNO 2 (Table 1) it was shown that in CH 2 Cl 2 , MeCN, or THF N nitrosoamine 4d prevailed in the reaction products, while MeOH changes this ratio in favor of N nitroamine 3d. The use of MeOH gives higher yields of N nitroamine 3d with other nitrite salts as well. Unlike the aprotic solvents, methanol no ticeably levels the influence of the cations, which later allowed using the most available NaNO 2 . The reaction in MeOH is weakly exothermic, the change in temperature from -20 °C to room temperature has little effect on the yield of products, the optimal reaction temperature is 0-5 °C.

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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)