Methane nitro-, reaction products with

In his dissertation (13), Goepp contributed to Professor Chattaway s classical organic program by studying the reaction of formaldehyde with p-nitrophenol. He determined that bis(6-nitro-l,3-benzodioxan-8-yl) methane (I) was one of the reaction products. 

Products. The product analyses for the reaction of nitronium hexafluorophosphate with aromatic amines were carried out by n. m. r. A solution of the nitronium salt and trinitrobenzene (as a standard material for n. m. r. analysis) in nitro-methane was added dropwise, with shaking, to a solution of an amine in the same solvent. After fifteen minutes the reaction mixture was poured into ether (50 ml), and any precipitate filtered off using a glass filter. The precipitate was dissolved in a small amount of acetone and analysed for the diazonium salt by n. m. r. The ether solution was washed with water, dried on magnesium sulphate and filtered using a filter paper. After evaporation of the solvent under reduced pressure, the products were dissolved in acetone or deuterated chloroform and analysed by n. m. r. 

Interestingly, we found that the CuBr-catalyzed aza-Heniy-type CDC reaction also proceeds well in ionic liquids under an ojygen atmosphere. The catalyst-containing ionic liquid can be re-used without loss of reactivity after extraction of the product with diethyl ether. Since ionic liquids are highly polar and excellent media for conducting electricity, we subsequently demonstrated that the CDC of Af-phenyltetrahydroisoquinoline with nitro-methane is also feasible under electrochemical conditions. The reaction... 

The simpler nitrop>arafIins (nitromethane, nitroethane, 1- and 2-nitroproj)ane) are now cheap commercial products. They are obtained by the vapour phase nitration of the hydrocarbons a gaseous mixture of two mols of hydrocarbon and 1 mol of nitric acid vapour is passed through a narrow reaction tube at 420-476°. Thus with methane at 476° a 13 per cent, conversion into nitro methane is obtained ethane at 420° gives a 9 1 mixture of nitroethane (b.p. 114°) and nitromethane (b.p. 102°) propane at 420° afifords a 21 per cent, yield of a complex mixture of 1- (b.p. 130-6°) and 2-nitropropane (b.p. 120°), nitroethane and nitromethane, which are separated by fractional distillation. 

Some solvents containing heavy atoms can induce enhancement of phosphorescence at the expense of fluorescence, e.g. ethyl iodide, nitro-methane, CS2 (external heavy atom effect). Irreversible conversion to ionic or radical products is often observed. Hence the system changes with time and the process should be classed a photochemical reaction distinct from the reversible quenching reactions discussed above. For example for anthracene and carbon tetrachloride ... 

This reaction must be brought about by heating to 90° to 100° C., and takes place very rapidly in alcoholic as well as aqueous solution. The product of the reaction, sodium nitro methane disulphonate, forms small spheroidal plates, soluble with difficulty in cold water but easily in hot water. According to Rathke, if the reactants are heated excessively a salt is obtained which no longer contains the NO — group and to which he attributes the formula CH(S03Na)3. 

Nitronium tetraHuoroborate and m dinitrobenzene were added to fluoro-sulphuric acid and cooled in a dry ice/acetone bath. The temperature was gradually raised to ISO C. After three hours of heating the reaction mixture was poured on to crushed ice. The nitro product was extracted with dichloro-methane, washed with sodium hydrogen carbonate solution and dried over magnesium sulphate. The yield of sym-trinitrobenzene was 61.6% with 5% unreacted m-dinitrobenzene. 

A 500 ml round bottom flask equipped with thermometer and overhead stirrer containing 150 ml of nitric acid (98 %) was cooled to 10 °C to which propane diurea 10 g (0.064 mol) was added slowly in small portions under constant stirring and cooling below 18 °C. The reaction mixtiue was stirred at this temperature for 5 min and then 75 ml of acetic anhydride (97 %) was added dropwise at 21 °C to 23 °C. Under this condition the stirring was continued for 8—9 h and finally filtered to yield a white compound which was washed thoroughly and dried. The reaction was monitored by IR spectrum in KBr matrix till the disappearance of the NH peak at 3258 cm. The yield of the fully converted nitramine product was 17.6g (82%). Recrystallization from nitro-methane gave a compound of m.p. > 220 °C (deflagration). With this optimized conditions the batch size was enhanced to 10—15g. The compound was fully characterized by IR, H-NMR and elemental analysis. DTA results showed the decomposition peak temperature at 235 °C. 

At high temperature (above about 400°C) alkanes undergo nitration with nitric acid (HONO2). The reaction has all of the characteristics of the radical processes already discussed and, except for methane (CH,) (Equation 6.10), the large number of products produced from most alkanes due to carbon-carbon bond cleavage and introduction of more than one nitro group (-NO2) Unaits the utility of the process. 

The earliest reported demonstration of enzymatic activity in a supercritical fluid was for the reaction of disodium p-nitrophenyl phosphate to p-nitro-phenol, catalysed by alkaline phosphatase. Randolph et aL [26] detected the product in yields of up to 71% in carbon dioxide at 35°C and 100 atm, in the presence of 0.1% v/v water. Hammond et al. [33] found tyrosinase, a polyphenol oxidase, to be catalytically active for the oxidation of 4-methyl phenol in both supercritical carbon dioxide at (36 2)°C and supercritical trifluoro-methane at (34 2)°C, with oxygen, at a total pressure of 345 bar. Use of a flow reactor permitted isolation of greater quantities of the catecholic product (1,2-dihydroxy, 4-methylbenzene). Oxidative activity for 4-chlorophenol substrate was appreciably lower. 

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