Ketones 1.3- dinitro compounds

Most nitroparaffins do not react with ketones, but ia the presence of alkoxide catalysts, nitromethane and lower aUphatic ketones give nitro alcohols ia the presence of amine catalysts dinitro compounds are obtained. 

In 1970, a new reacdon, the displacement of a nitro group from ct-nitro esters, ct-nitro nitnles, ct-nitro ketones, iind ct,ct-dinitro compounds by nitroalkiine salts, was described. These displacements, which are exemplified by the reacdon presented in Eq. 7.1, take place at room temperanire iind give excellent yields of pure products. The reacdon proceeds via a radiciil chain mechanism involving one electron-transfer processes as shovmin Scheme 7.1 the details of the mechanism are described in a review. ... 

Among organic materials, poly(aryl ethers) and poly (aryl sulfides) have been known, as a class of engineering thermoplastics. The electron withdrawing sulfone and ketone groups usually activate the dihalo or dinitro compounds to facilitate the nucleophilic displacement through the transition state called Meisenheimer-Iike complex, and, thus, poly(aryl ether or sulfide) sulfones... 

Peroxyacids are powerful oxidants and so side reactions are to be expected. Ketones are known to undergo Baeyer-Villiger " oxidation to the carboxylic acid ester on treatment with peroxyacids and so these by-products can be observed if oxime hydrolysis occurs during the oxidation. Paquette and co-workers " " observed such a by-product (61) during the oxidation of the dioxime (59) to the dinitro compound (60) with m-CPBA in hot acetonitrile. 

When olefins are treated with N204 in an ether, ester, or alkane as solvent, vtc-dinitro compounds and 3-nitro alkyl nitrites are produced.803 The reaction can be successfully performed with all kinds of olefins and acetylenes. Generally, both products are produced. The dinitro compound is usually stable, but the ester is quite reactive. Upon addition of water or alcohol it is hydrolyzed to a 3-nitro alcohol. If oxygen is added, it is oxidized to a 3-nitro alkyl nitrate or an a-nitro aldehyde or ketone. 

Oximes of carbocyclic ketones in hydrogen carbonate solution are oxidized by jV-bromosuccinimide to 1-bromo-l-nitrosocycloalkenes, which are converted by nitric acid into 1-bromo-l-nitrocycloalkanes in 40-70% yield, and the latter products can be reduced by potassium iodide in methanol or by sodium tetra-hydridoborate to the corresponding nitrocycloalkanes.197 Oximes of aromatic aldehydes may be converted by dinitrogen tetraoxide into the dinitro compounds.198 tt-Nitrobenzaldehyde oxime is converted by dinitrogen tetraoxide into oc,ot, -trinitrotoluene (phenyltrinitromethane) in 77% yield.199... 

The nitration of active methylene compounds by the action of nitrate esters under basic conditions is a general and convenient method for introducing a nitro group in o-position to the activated group. The pioneering work of Thiele [93] and Wislicenus [94] should be added to the previously (Vol. I) mentioned papers. Also the work of Wieland and associates [9S] should be mentioned as producing the dipotassium salt of dinitro cyclic ketones, according to equation (33) ... 

In alkaline medium, dialkylphosphites react with m-dinitrobenzene and other aromatic m-dinitro compounds forming a blue to purple color. Methyl-ketones react similarly and must be absent. 

Reaction of Methyl Ketones with m-Dinitro Compounds... 

In the literature the name of Janovsky is connected with the reaction of aromatic polynitro compounds, especially those of m-dinitro compounds with alkalies in the presence of compounds with an active methylene group (--CH2—) —for example, methyl ketones. An orange, red, or violet to blue color appears, depending on the nature of the polynitro compound (see also p. 234) (12, 13). 

Nucleophilic displacement of an activated dihalo or dinitro compound with an activated bisphenoxide salt at high temperatures has been the most explored method of poly (aryl ether) synthesis [62], These synthetic strategies were further extended for the preparation of hb poly(aryl ether)s in one-step polymerization from AB2 monomers containing a phenolic group and two aryl fluorides, which were activated toward nucleophilic displacement by a sulfone, ketone, imide, or heterocycle [63-65]. Miller et al. [63], Hawker and Chu [65], and Shu and Leu [66] reported the synthesis of hb poly(aryl ether ket(Mie)s (hb-PAEKs) via the AB method. The structures of AB2 monomers reported by Hawker and Chu [65] are shown in Scheme 4 (1-5 and 1-6). The structiu es of AB2 monomers reported by Shu and Leu [66] are shown in 1-7, Scheme 4. 

In order to characterize them and more readily separate them from interfering accompanying substances carbonyl compounds (aldehydes, ketones) can be converted to hydrazones at the start. The reagent mainly employed is 2,4-dinitro-phenylhydrazine in acidic solution [70], This yields osazones with aldoses and ketoses. Some examples are listed in Table 15. 

Recently, Dutta and Maiti [21] reported nitro displacement polymerization of the bisphenol dianion with the sulfone activated dinitro aromatic compounds. In addition, there have been recent reports of the development of functionalized PEEK [22] and polyether sulfone ketone (PESK) [23] that are comparable to commercially available high performance polymers. 

Nitroenamines and related compounds have been used for synthesis of a variety of heterocyclic compounds. Rajappahas summarized the chemistry of nitroenamines (see Section 4.2).140 Ariga and coworkers have developed the synthesis of heterocycles based on the reaction of nitropyridones or nitropyrimidinone with nucleophiles. For example, 2-substituted 3-nitro-pyridines are obtained by the reaction of l-methyl-3,5-dinitro-2-pyridones with ketones in the presence of ammonia (Eq. 10.82).141... 

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. °... 

Subsequently, Tselinskii et al. found the dianion of Compound 2a to be stable and reacted it with a variety of electrophiles including picryl chloride, acetic anhydride, methyl iodide and vinyl ketone. They synthesized its dinitro derivative, dinitrodifurazano piperazine (2b) (DNDFP) [Structure (2.63)] by reacting the dianion (2a) with nitrogen oxide in CH3CN. The dinitro derivative which is quite reactive, was isolated by column chromatography and confirmed by mass spectroscopy [272]. 

However, in some cases azines can be converted to hydrazones by treatment with excess hydrazine and NaOH.202 Arylhydrazines, especially phenyl, p-nitrophenyl, and 2.4-dinitro-phenyl,203 are used much more often and give the corresponding hydrazones with most aldehydes and ketones.204 Since these are usually solids, they make excellent derivatives and are commonly employed for this purpose. a-Hydroxy aldehydes and ketones and a-dicar-bonyl compounds give osazones, in which two adjacent carbons have carbon-nitrogen double bonds ... 

When unknown compounds are identified without the aid of spectroscopy classification tests are used. Reacting the carbonyl in a ketone or aldehyde with an amine (2,4 dinitro-phenylhydrazine) to form an inline is the easiest way to detect a ketone or aldehyde (Reaction l). The iinine that forms is a highly colored solid. The color of the solid also helps to indicate structural characteristics. Ketones and aldehydes with no conjugation tend to form itnines with yellow to orange colors, while highly conjugated ketones or aldehydes form imines with red color. 

Most classes of VOCs found in indoor environments are sampled onto sorbents by adsorption but highly reactive VOCs like carbonyl compounds are sampled by chemical reactions with the sorbent. Thus aldehydes and ketones are sampled by their reactions with sorbent gels coated with 2,4-dinitro-phenylhydrazine to form stable hydrazones [38-40]. Similarly, formaldehyde has been sampled by its reaction with N-benzylethanolamine to give 3-benzyl-oxazolidine [41,42]. 

Chemist 2 conducted qualitative tests for some carbonyl compounds. Aldehydes and ketones gave a positive test for the reagent 2,4-dinitro-... 

It has been extended to other ketones. Sometime later, it was discovered that this reaction is positive with molecules possessing an active methylene, such as a-methylene ketones. Zimmermann applied it to 17-ketosteroids of great pharmacological interest. Numerous experimental modifications have been proposed, including the use of organic bases instead of potassium hydroxide and the use of other nitro derivatives of benzene. It seems well established that when m-dinitro or 1,3,5-trinitrobenzene reacts with an excess of a compound possessing an active methylene in basic medium, a o Meisenheimer complex forms ... 

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