Nitroacetic acid

According to the Friedlander method, the condensation of the readily available 2-aminoiiicotinic aldehyde (20a) (74JOC726) or its 6-phenyl derivative (20b) [66JCS(C)315] with nitroacetic acid (21) in boiling ethanol with piperidine as catalyst is another example of this method, which affords in fair yields the corresponding 3-nitro-l,8-naphthyridin-2(lFI)-ones (22a, 74%) and (22b, 47%), respectively [66JCS(C)315]. 

Na hydroxide first forms the Na salt of NMe, then the Na salt of methazonic acid, and finally the Na salt of nitroacetic acid (Ref 10). 5) With Hg(ll) chloride is formed first the Hg salt of NMe which rearranges and dehydrates to MF (Ref 10). 

Cklorodifluoronitrosomethane. ClCF2NO, mw 115.47 N 8.24% a dark blue liq or gas bp ca -35° (Refs 1, 2 6) CA Registry No 421-13-6 Preparation. It has been prepd by reactions analogous to those for prepn of trifluoronitrosomethane (Refs 2 5). It has also been prepd by the action of 33% aq nitric acid on chloro-difluorosulfenyl chloride (C1CF2SC1) (Ref 3), and by the action of hot coned HC1 on difluoro-nitroacetic acid (Ref 4). Its props and reactions are similar to trifluoronitrosomethane Refs 1) Beil 1, <99) 2) R.N. Hazeldine, JCS... 

Nitroacetic Acid. See Vol 1, A27-R under Acetic Acid and Derivatives. Its dipotassium salt, which is expl is briefly described, whereas its other expl salts, such as Pb, Ag and Hg are only mentioned. All of these salts are described by W. Steinkopf in Ber 42, 2026-31 (1909) CA 3,1438(1909)... 

Nitroacid. A compd containing both the radicals —COOH and —N02. Some of these are expl, eg, Nitroacetic Acid, 02N.CH2.COOH Dinitro-benzoic acid, (02N)2.C6H3.COOH Triiutro-benzoic acid, (02N)3.C6H2.COOH etc Ref Hackh s (1972), 457-R... 

B. Methyl Nitroacetate. A 2-1., three-necked, round-bottomed flask equipped with a sealed mechanical stirrer, a pressure-equalizing dropping funnel fitted with a calcium chloride drying tube, and a thermometer is charged with 70 g. (0.387 mole) of finely powdered dipotassium salt of nitroacetic acid (Note 4) and 465 ml. (11.6 moles) of methanol. 

Methyl nitroacetate has been prepared from nitromethane through the dipotassium salt of nitroacetic acid by the classical Steinkopf method3 but in lower yield. The dipotassium salt was obtained in 45% yield. The method has been improved by Matthews and Kubler4 but the salt must be recrystallized prior to esterification. 

Application of sulfuric acid as the catalyst is considered more practical for esterification because of its higher boiling point, its incompatibility with benzene, and the stability of nitroacetic acid in the reaction mixture that allows the omission of the final neutralization step. 

Field Effects. These were discussed on page 16. As an example of the influence of field effects on acidity, we may compare the acidity of acetic acid and nitroacetic acid ... 

The isoxazoles can also be prepared in stepwise manner from the epoxyaldehydes 7-55 using a-nitroacetic acid derivatives and DIPEA, though the yields are much lower. 

The carboxylation of nitroalkanes with magnesium methyl carbonate followed by esterification gives a-nitro esters in 40-58% yield.14 Magnesium methyl carbonate is prepared by the saturation of a magnesium methoxide suspension in DMF with C02. More elegantly, sodium salt of nitroalkanes can he carboxylated by means of 1 -ethoxycarbonylbenzotriazole to give a-nitro esters in 55-80% yield (Eq. 5.7).15 Nitroacetic acids and its esters can serve as useful... 

The preparation of resin-bound nitroalkenes via a microwave-assisted Knoevenagel reaction of resin-bound nitroacetic acid with aryl and alkyl substituted aldehydes is reported. The potential of these resin-bound nitroalkenes for application in combinatorial chemistry is demonstrated by a Diels-Alder reaction with 2,3-dimethylbutadiene (Scheme 8.9). It is also used for one-pot three-component tandem [4+2]/[3+2] reactions with ethyl vinyl ether and styrene 46... 

Microwave-assisted Knoevenagel reactions have also been utilized in the preparation of resin-bound nitroalkenes [56], The generation of various resin-bound nitroalkenes employing resin-bound nitroacetic acid has been described the latter was condensed with a variety of aldehydes under microwave conditions (Scheme 7.40). 

By the action of thionyl chloride Steinkopf prepared from this substance the long-sought nitroacetonitrile 2 N02.CH2.CN, and by the hydrolysis of this nitrile, nitroacetic acid.3... 

M. T. Shipchandler, The Utility of Nitroacetic Acid and its Esters in Organic Synthesis, Synthesis 1979, 666. A.G. Agababyan, G.A. Gevorgyan u. O. L. Mndzhoyan, Amino Acids as the Amine Component in a Mannich Reaction, Usp. Khim. 51, 678 (1982). 

Nitroacetic Acid (Nitroathansaure or Nitro-essigsaure, in Ger), 02N.CH2. COOH, mw 105-05, N 13.33%. Ndls, expl on heating sol in chlf, benz toluene insol in petr eth decompd by w yields nitromethane when heated with w. Was prepd from the dipotassium salt (see below) and dry HC1 in ether (Refs 1 3)... 

Dipotassium Salt of Nitroacetic Acid A27-R Disol. See 2,4-Dinitroanisole A448-L Distyrylazobenzene. See Azostilbene A65S> R N1,N -(Ditetrazolyl-5)-hexazadiene A260-R Dithiocarbonic or Ditbioformic Acid, Azido Derivatives A632... 

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