Nitroethanols

Nitroethylene Dehydration of l-nitroethanol using phthahc anhydnde f80% is the best choice of preparation bp 38-39 C/80 mm Hg. 

The reaction with nitroethanol in the presence of di-)i-bntylammmonium chloride in refluxing iropentyl acetate gives 2-unsnbsdtnted 3-nitro-2H-chromene in 50% yield. Some 3-nitro-2H-chromenes display efficient optical second harmonic generadon for nonhnear opdcal apphcations. 

Sodium (3-Nitroethanol Methyl dichloroacetate Acetic anhydride... 

The synthetic route to chloramphenicol is described in U.S. Patent 2,4B3,BB4 as follows 1.1 g of sodium is dissolved in 20 cc of methanol and the resulting solution added to a Solution of 5 g of benzaldehyde and 4.5 g of /3-nitroethanol in 20 cc of methanol. After standing at room temperature for a short time the gel which forms on the mixing of the reactants changes to a white insoluble powder. The precipitate is collected, washed with methanol and ether and then dried. The product thus produced is the sodium salt of... 

Distilling 2-nitroethanol gave rise to a detonation, which was explained by the accidental presence of a base in the distillation apparatus. 

Figure 5-3. Biocides bromo-2-nitropropane, 1-N-hexadecyl-1,2,4-tri-azole bromide, 3-hydroxy-4-methylthiazol-2(3H)-thione, 3-hydroxy-4-phenylthiazol-2(3H)-thione, 2,3-dibromo-1-chloro-4-thiocyanato-2-butene, 1,2-dibromo-2,4-dicyanobutane, 2,2-dibromo-2-nitroethanol.

Interaction of nitromethane and formaldehyde in presence of alkali gives not only 2-nitroethanol, but also di- and tri-condensation products. After removal of the 2-nitroethanol by vacuum distillation, the residue must be cooled before admitting air into the system to prevent a flash explosion or violent fume-off. 

An explosion occurred towards the end of vacuum distillation of a relatively small quantity of 2-nitroethanol. This was attributed to the presence of peroxides, but the presence of traces of alkali seems a possible alternative cause. 

Tetrahydropyranyl (THP)-protected nitroethanol can be doubly deprotonated to lithium a-lithionitronate, which is stable to react with various electrophiles. Higher P-nitro alcohols,... 

The use of silylketals derived from allylic alcohols and 1-substituted nitroethanols for the stereocontrolled synthesis of 3,4,5-trisubstituted 2-isoxazolines via intramolecular 1,3-dipolar cycloaddition has been demonstrated. Here again, the use of silyl nitronates (ISOC) increases the level of selectivity compared to INOC (Eq. 8.92).145... 

Kambe and Yasuda19 discovered the effectiveness of the fluoride as a Henry reaction catalyst. Since then, the use of diverse fluorides is a common method to catalyze nitro aldol condensations, since they provide mild conditions that are particularly convenient for sensitive products as carbohydrates. The most common fluorides are potassium fluoride20 and tetrabutyl ammonium fluoride.21 A recent example relates to the TBAF catalyzed addition of nitroethanol to the D-glucose derivative 18, to give nitro sugars 19 (Scheme 8).22... 

The reaction of alkynes with nitric acid or mixed acid is generally not synthetically useful. An exception is the reaction of acetylene with mixed acid or fuming nitric acid which leads to the formation of tetranitromethane. A modification to this reaction uses a mixture of anhydrous nitric acid and mercuric nitrate to form trinitromethane (nitroform) from acetylene. Nitroform is produced industrially via this method in a continuous process in 74 % yield. " The reaction of ethylene with 95-100 % nitric acid is also reported to yield nitroform (and 2-nitroethanol). The nitration of ketene with fuming nitric acid is reported to yield tetranitromethane. Tetranitromethane is conveniently synthesized in the laboratory by leaving a mixture of fuming nitric acid and acetic anhydride to stand at room temperature for several days. ... 

The reaction of a -halocarboxylic acids with sodium nitrite has been used to synthesize ni-tromethane, nitroethane and nitropropane, although the reaction fails for higher nitroalkanes. " A number of other reactions have been reported which use nitrite anion as a nucleophile, including (1) reaction of alkyl halides with potassium nitrite in the presence of 18-crown-6, (2) reaction of alkyl halides with nitrite anion bound to amberlite resins, (3) synthesis of 2-nitroethanol from the acid-catalyzed ring opening of ethylene oxide with sodium nitrite, and (4) reaction of primary alkyl chlorides with sodium nitrite in the presence of sodium iodide. ... 

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... 

For the cyclization of dialdehydes, however, its utility seems limited. Being a nitromethane addition product, it can readily undergo retro-nitromethane addition with alkali to give formaldehyde and nitromethane. Thus, it is not surprising that reaction of glutaraldehyde with 2-nitroethanol under the usual conditions (i.e. 1 molar equivalent of sodium hydroxide in aqueous ethanol) should yield 2-nitrocyclohexane-1,3-diol 5), a nitromethane cyclization product With catal5dic amounts of sodium hydroxide (pH 8—9), however, 1-hydroxymethyl-l-nitro-cyclohexane-2-6-diol (80) can be isolated in yields of 24—29%... 

The second method consists of the condensation of diacetate of the same aldehyde with nitromethane, which forms (3,4-diacetoxyphenyl)-2-nitroethanol (11.1.5). Then the nitro group is reduced and the product (11.1.6) is hydrolyzed into the desired norepinephrine (11.1.4) [4,9,13,14]. 

V.M. Bashinova, NeftepererabNeftekhim 1, 21—3 (196S)(Russ) CA 68, lO4503(1968)(Phys props of 2-Nitroethanol) 11) Ibid, ZhPriklKhim 41 (8),... 

EthanoJ,2-Nitronitrate 2-Nitroethanol Nitrate l-Nitroxy-2-nitroethane or 9-Nitroethyl Nitrate,... 

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