1,3-Dinitro compounds aliphatic

Aliphatic dinitro compounds, nitronitric acid esters, and nitroalcohols from olefins... 

For aromatic or heteroaromatic monoaldehydes, ArCHO, an efficient procedure has been developed for synthesis of 1,3-dinitro compounds [132]. Rather than in situ reduction of O2, the O2 reduction is carried out in a divided cell with the aliphatic nitro compound as the solvent. Charge corresponding to 0.5 F with respect to the aldehyde is passed through the cell, the current is switched off... 

The Ponzio reaction provides a useful route to gem-dinitro compounds and involves treating oximes with a solution of nitrogen dioxide or its dimer in diethyl ether or a chlorinated solvent. The Ponzio reaction works best for aromatic oximes where the synthesis of many substituted aryldinitromethanes have been reported. Compound (56), an isomer of TNT, is formed from the reaction of dinitrogen tetroxide with the oxime of benzaldehyde (55) followed by mononitration of the aromatic ring with mixed acid. Yields are usually much lower for aliphatic aldoximes and ketoximes. " The parent carbonyl compound of the oxime is usually the major by-product in these reactions. 

Alcantara, M.-P.D., Dianez, M.J., Escribano, F.C., Estrada, M.D., Gomez-Sanchez, A., Lopez-Castro, A., and Perez-Garrido, S. 1996. Synthesis of aliphatic 1,3-dinitro compounds. Synthesis, 1 64-70. 

Olefin synthesh. Komblum ei a . have described a new synthesis of tetrasubsti-tuted olefins from vicinal dinitro compounds. There are several methods for conversion of aliphatic and alicyclic nitro compounds into nic-dinitro compounds, the most useful of which is a procedure of Seigle and Hass. A nitroparafhn is converted into (he lithium salt (I) by treatment with lithium methoxidc and this is then treated with bromine to form a bromonilro compound (2). Reaction of (2) with a second equivalent of the nitro-R.. NO,, ... 

Aliphatic gem-dinitro compounds can be prepared by anodic oxidation of a nitro-paraffin in aqueous alkaline solution in the presence of an excess of N02 [201]. Yields are considerably better when Ag" is the oxidizing agent [202], so that an indirect oxidation process involving the generation of Ag" " at an Ag anode was found to give excellent results [203]. 

Problem 24.8 The //-propyl ether of 2-amino-4-nitrophenol is one of the sweetest compounds ever prepared, being about 5000 times as sweet as the common sugar sucrose. It can be made from the dinitro compound by reduction with ammonium bisulfide. Outline the synthesis of this material starting from benzene or toluene and any aliphatic reagents. 

Niazimbetova ZI, Evans DH, Liable-Sands LM, Rheingold AL (2000) Electrochemical synthesis of aliphatic 1,3-dinitro compounds. J Electrochem Soc 147 256-259... 

Aliphatic geminal dinitro compounds are obtained by oxidative nitration of mononitro compounds with silver nitrate and sodium nitrite in an alkaline medium.165... 

Denitration of ic-dinitro compounds. ra -StiIbene (2) and 9,9 -bifluor-enylidene (4) can be obtained by denitration of (1) and (3), respectively, with anhydrous stannous chloride or the dihydrate (4 eq.). This method fails in the case of aliphatic v/c-dinitro compounds. ... 

Potassium hydroxide alcohol Aliphatic 1,3-dinitro compounds... 

Silver nitrate/sodium nitrite sodium hydroxide 1,1-Dinitro compounds from aliphatic nitro compounds... 

Synthesis of aliphatic 1,3-dinitro compounds from 1,2-nitramines... 

Aliphatic nitro compounds are hydrolyzed, with the formation of nitrous acid, which can be detected easily. The reaction is also given with aromatic o- and p-dinitro compounds containing a labile nitro group (3). 

Various hypotheses have been put forward concerning the mechanism of this reaction. It seems that the reaction is rather complicated, and that the reaction of polynitro compounds with alkalies in alcohol (14, 15,16), as well as the reaction of dinitro compounds with aliphatic amines and diamines, most recently carried out in dimethylformamide or dimethyl sulfoxide, or the reaction with alkali cyanides, also belong to this type of color reactions. 

Useful for other arohiati c vic-dinitro compounds but fails with aliphatic vic-dinitro compounds. 

Du and coworkers have developed a stereoselective direct Michael addition of nitroalkanes to nitroalkenes catalyzed by quinine-derived dimeric squaramide 21 [93]. This transformation provided facile access to 1,3-dinitro compounds in high diastereo- and enantioselectivities starting from aryl-substituted nitroalkenes (Scheme 10.18). However, the use of an aliphatic nitroalkene as Michael acceptor resulted in a low yield and diminished enantioselectivity. While nitroethane and 1-nitropropane are excellent substrates, branched 2-nitropropane did not undergo the Michael addition reaction. The authors also noted that slightly reduced dias-... 

Aliphatic compounds containing terminal gem-dinitro functionality form adducts with Michael acceptors.Of particular interest is the reaction of a,a,o),a)-tetranitroalkanes with Michael acceptors. ° Most a, o, y, y-tetranitroalkanes will react with two equivalents of Michael acceptor to form bis-adducts, like in the case of 1,1,4,4-tetranitrobutane, which reacts with two equivalents of methyl vinyl ketone, methyl acrylate, acrylonitrile etc. ° The influence of steric effects becomes apparent with a,a,y,Y-tetranitroalkanes, like 1,1,3,3-tetranitropropane, which can form either mono-adducts or bis-adducts depending on the Michael acceptor used 1,1,3,3-tetranitropropane will only react with one equivalent of methyl acrylate and the sole product of this reaction is methyl 4,4,6,6-tetranitrohexanoate. °... 

Both the Henry reaction and the reverse demethylolation are synthetically useful in the chemistry of polynitroaliphatic compounds. The Henry reaction is commonly used to mask the natural chemistry of an aliphatic nitro or terminal em-dinitro group by removing the acidic a -proton(s). In Section 1.7 we discussed the conversion of Q ,ty-dinitroalkanes to their bis-methylol derivatives before subjecting them to oxidative nitration and subsequent demethylolation with base, a procedure which results in the formation of Q ,Q , y, y-tetranitroalkanes. ... 

A new general method of preparing polynitro aliphatic compounds was recently described by Frankel [92], The reaction consists in acting with 2-bromo-2,2-dinitro-ethyl acetate (I) on metallic salts of organic and inorganic compounds having active hydrogen atoms. 

Group / Liquid aliphatics with relatively symmetrical substitutions around the main chain. Figure 5.1 shows an example of this in the compound 1,3-dinitro-propane. The nitro groups are at each end of the molecule, and the molecule is said to be symmetrical. Another example, given in Figure 5.2, is 2,2-dinitropro-pane. Here also, the substituents are symmetrically placed on the main chain. Also included in this group are those molecules that have two or more kinds of substituents, even if they are not placed exactly symmetrically. 

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