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Nitromethane, preparation reactions

Nitromethane, CH3NO2, the first member of the homologous series, can, however, be readily prepared by a special reaction. When equimolecular amounts of sodium nitrite and sodium monochloroacetate are heated together in aqueous solution, the chlorine in the monochloroacetate is replaced by the nitro group, and the sodium nitroacetate thus formed undergoes hydrolysis follow ed by decarboxylation ... [Pg.131]

Nitromethane is more easily prepared by heating together equimolecular amounts of sodium monochloroacetate and sodium nitrite in aqueous solution sodium nitroacetate is intermediately formed and is decomposed to nitromethane and sodium bicarbonate. The latter yields sodium carbonate and carbon dioxide at the temperature of the reaction. [Pg.302]

Nitrofurantoin. The urinary tract antibacterial, l-[(5-nitro-2-furanyl)-methyleneamino]-2,4-imidazohdinedione, is prepared by reaction of 5-nitro-2-furancarboxaldehyde with l-anaino-2,4-imidazohdinedione (19,40). Crystallization of the material from nitromethane provides a macrocrystalline form (41) which continues to be employed clinically. [Pg.461]

C-Alkyldtkin takes place in the reaction of methyl nitroacetate with ilkyl h ilicles the products are useful intermediates for preparing amino acids fEq. 5.1 /The requisite nitro acetate is prepared by seif condensadon of nitromethane. ... [Pg.127]

Recently, the Texier-Boullet group [26] has prepared nitrocyclohexanols 10-77 by a twofold Michael addition/aldol reaction sequence (Scheme 10.19). Simply mixing chalcone 10-75 with nitromethane in the presence of a mixture of KF and A1203 under microwave irradiation gave 10-79 via the proposed intermediates 10-76, 10-77 and 10-78 as a single diastereomer in 65 % yield. One possible explanation for the stereoselectivity of the transformation is fixation of the reactive species onto the solid KF/A1203, as depicted in 10-79. [Pg.577]

Combining, in tandem, the nitro-aldol reaction with the Michael addition using thiophenol is a good method for the preparation of P-nitro sulfides as shown in Eqs. 4.2 and 4.3. This reaction is applied to a total synthesis of tuberine. Tuberine is a simple enamide isolated from Streptomyces amakusaensis and has some structural resemblance to erbastatin, an enamide which has received much attention in recent years as an inhibitor of tyrosine-specific kinases. The reaction of p-anisaldehyde and nitromethane in the presence of thiophenol yields the requisite P-nitro sulfide, which is converted into tuberine via reduction, formylation, oxidation, and thermal elimination of... [Pg.79]

Nitroacetaldehyde diethyl acetal is prepared by the reaction of nitromethane with triethyl orthoformate in the presence of ZnCl2 (Eq. 5.8).17 Jager and coworkers have used this reagent for the synthesis of amino sugars via nitro-aldol reaction.18 Preparation of this useful reagent is now described in volume 74 of Organic Synthesis.19... [Pg.129]

The reaction of tertiary nitro compounds with the sodium salt of nitromethane followed by the Nef reaction provides a good method forthe preparation of quaternary aldehydes (Eq. 7.10).8 Because the nitromethyl group can be transformed into other groups such as CN, C02H, or CH2NH2, the SRN I reaction of tertiary nitro compounds with the anion of nitromethane is a synthetically useful method (Kornblum reaction).10 For example, the nitromethylation of tertiary nitro compounds has been applied for preparing starting materials for cascade polymers (Eq. 7.11).9... [Pg.184]

Ono and coworkers have extended the radical elimination of v/c-dinitro compounds to P-nitro sulfones151 and P-nitro sulfides.138,152 As P-nitro sulfides are readily prepared by the Michael addition of thiols to nitroalkenes, radical elimination of P-nitrosulfides provides a useful method for olefin synthesis. For example, cyclohexanone is converted into allyl alcohol by the reaction shown in Eq. 7.110. Treatment of cyclohexanone with a mixture of nitromethane, PhSH, 35%-HCHO, TMG (0.1 equiv) in acetonitrile gives ahydroxymethylated-P-nitro sulfide in 68% yield, which is converted into the corresponding allyl alcohol in 86% yield by the reaction with Bu3SnH.138 Nitro-aldol and the Michael addition reactions take place sequentially to give the required P-nitro sulfides in one pot. [Pg.216]

Dithio-l-nitroalkenes are prepared by the reaction of nitromethane with CS2 and KOH followed by alkylation with alkyl halides (Eq. 10.84).43 They are important reagents for synthesis... [Pg.356]

Water is involved in most of the photodecomposition reactions. Hence, nonaqueous electrolytes such as methanol, ethanol, N,N-d i methyl forma mide, acetonitrile, propylene carbonate, ethylene glycol, tetrahydrofuran, nitromethane, benzonitrile, and molten salts such as A1C13-butyl pyridium chloride are chosen. The efficiency of early cells prepared with nonaqueous solvents such as methanol and acetonitrile were low because of the high resistivity of the electrolyte, limited solubility of the redox species, and poor bulk and surface properties of the semiconductor. Recently, reasonably efficient and fairly stable cells have been prepared with nonaqueous electrolytes with a proper design of the electrolyte redox couple and by careful control of the material and surface properties [7], Results with single-crystal semiconductor electrodes can be obtained from table 2 in Ref. 15. Unfortunately, the efficiencies and stabilities achieved cannot justify the use of singlecrystal materials. Table 2 in Ref. 15 summarizes the results of liquid junction solar cells prepared with polycrystalline and thin-film semiconductors [15]. As can be seen the efficiencies are fair. Thin films provide several advantages over bulk materials. Despite these possibilities, the actual efficiencies of solid-state polycrystalline thin-film PV solar cells exceed those obtained with electrochemical PV cells [22,23]. [Pg.233]

First SENA was prepared by Klebe in 1964 by the reaction of nitromethane with iV-trimethylsilyl-A.A -diphenylurea (171) (Scheme 3.49). [Pg.469]

Reaction of nitromethane and monosaccharide-derived dialdehydes is a useful tool that has been broadly used for the preparation of nitro and amino sugars, and carbocycles.30 Dialdehydes can easily be obtained by oxidative cleavage of conveniently protected monosaccharides with sodium periodate. Their subsequent Henry reaction with a nitroalkene, commonly nitromethane, usually gives isomeric mixtures that require the isolation of the major isomer.31 Thus, treatment of the D-ribose derivative 27 with sodium periodate gave dialdehyde 28, which was subjected to a Henry reaction with nitromethane, to afford nitrosugar 29 as an epimeric mixture (Scheme 11).32... [Pg.176]

Nitromethane is the most easily accessible aliphatic nitro-com-pound Kolbe s method of preparation is much less satisfactory when applied to higher members of the series. The course of the reaction is clear, and the reasons for the decomposition which takes place are similar... [Pg.156]

As in the case of other groups which activate adjacent CH6, the nitro group in aliphatic nitro compounds soon acquired importance in preparative organic chemistry, particularly for condensation reactions. The condensing agents are normally bases. Thus nitromethane will react with benzaldehyde to give first a nitro-alcohol and then a nitro-olefin (Priebs, 188425) ... [Pg.482]

Triphenylnitrobenzene may be prepared by direct nitration of 1,3,5-triphenylbenzene and by the reaction of 2,4,6-triphenylpyrylium tetrafluoroborate with nitromethane. The present procedure is an adaptation of the latter method. [Pg.140]

Besides solvation, a solvent can also participate in entrainment of ion-radical transformations. The reaction between tertiary aliphatic nitro compounds and the sodium derivative of nitromethane, NaCH2N02, is an example (Kornblum and Erickson 1981). To prepare NaCHjNOj, nitromethane is treated with sodium hydride. Then a tertiary aliphatic nitro compound is introduced into the solution formed. Several organic solvents were probed and CHjSOjCHj (DMSO) turned out to be the most effective. Kornblum and Erickson (1981) attributed this result to the formation of small amounts of NaCH2SOCH3 (sodium dimsyl) that was produced from DMSO as a result of its reaction with sodium hydride. Sodium dimsyl acts as a powerful one-electron reducer that induces the following chain anion-radical process ... [Pg.297]

Like nitromethane, 2-nitroethanol can be used as the methylene component for addition to aldehydes, giving epimeric nitrodiols in which the carbon chains have been lengthened by two carbon atoms. This reaction has attained preparative importance for the S5mthesis of higher-carbon ketoses 43,44) heptulose-phosphates 5) and of chloramphenicol... [Pg.203]


See other pages where Nitromethane, preparation reactions is mentioned: [Pg.21]    [Pg.46]    [Pg.224]    [Pg.378]    [Pg.66]    [Pg.44]    [Pg.299]    [Pg.329]    [Pg.264]    [Pg.361]    [Pg.17]    [Pg.17]    [Pg.264]    [Pg.368]    [Pg.7]    [Pg.31]    [Pg.63]    [Pg.152]    [Pg.329]    [Pg.120]    [Pg.219]    [Pg.849]    [Pg.512]    [Pg.188]    [Pg.158]    [Pg.320]    [Pg.482]    [Pg.243]    [Pg.46]    [Pg.208]   
See also in sourсe #XX -- [ Pg.133 ]




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