603-06-5Relevant academic research and scientific papers
Nitration of deactivated aromatic compounds via mechanochemical reaction
Wu, Jian-Wei,Zhang, Pu,Guo, Zhi-Xin
supporting information, (2021/05/05)
A variety of deactivated arenes were nitrated to their corresponding nitro derivatives in excellent yields under high-speed ball milling condition using Fe(NO3)3·9H2O/P2O5 as nitrating reagent. A radical involved mechanism was proposed for this facial, eco-friendly, safe, and effective nitration reaction.
Continuous-Flow Nitration of o-Xylene: Effect of Nitrating Agent and Feasibility of Tubular Reactors for Scale-Up
Sharma,Joshi,Kulkarni
, p. 1138 - 1147 (2015/09/28)
Continuous-flow nitration of o-xylene has been studied with different nitrating agents over a wide range of conditions for different parameters such as temperature, residence time, and concentrations. A nitrating mixture comprising sulfuric acid and fuming nitric acid was seen to yield higher selectivity for the isomer 1,2-dimethyl-3-nitrobenzene over the isomer 1,2-dimethyl-4-nitrobenzene and also a non-negligible quantity of dinitro derivatives of o-xylene. With only fuming nitric acid as the nitrating agent, the reaction was selective for 1,2-dimethyl-4-nitrobenzene over 1,2-dimethyl-3-nitrobenzene. Impurities mainly come from nitration of mononitro derivatives, and this occurs more from nitration of the 3-nitro isomer because of its higher reactivity with nitric acid. An economic analysis of the continuous-flow reactor for the production of 1,2-dimethyl-4-nitrobenzene at 100 and 500 kg/h in a jacketed tubular reactor showed that numbering-up is a more economical approach for higher production capacity. A combination of large- and small-sized tubes depending upon the relative rates of heat generation during a reaction will achieve more profit and a shorter payback period than having the entire reactor made of a single tube size.
ipso Nitration. XXVI. Nitration of 1,2-dimethyl-4-nitrobenzene. Formation and reactions of adducts
Fischer, Alfred,Henderson, George N.,Iyer, Lokanathan M.
, p. 2390 - 2400 (2007/10/02)
Nitration of 1,2-dimethyl-4-nitrobenzene in a mixture of acetic anhydride and trifluoroacetic anhydride gives the diastereoisomers of 4,5-dimethyl-2,4-dinitrocyclohexa-2,5-dienyl acetate (50percent), in addition to the 1,2-dimethyldinitrobenzenes.In moderate and more strongly acid conditions the adduct gives 4-nitro-, 3,4-dinitro-, and 3,5-dinitro-o-xylene.In neutral and weakly acid solutions 4-nitro- and 3,5-dinitro-o-xylene are formed by a radical and a sigmatropic pathway.The adduct reacts facilely with nucleophiles by allylic substitution to give a 5,6-dimethyl-6-nitrocyclohexa-2,4-dienyl derivative which, in many instances, undergoes a second allylic substitution to a new 4,5-dimethyl-2,4-dinitrocyclohexa-2,5-dienyl derivative.Depending on the nature of the introduced substituent, these 2,4- and 2,5-dienyl products may eliminate nitrous acid, under the reaction conditions, to give the corresponding aromatic compound.The dienyl acetates undergo acid-catalysed transesterification to the corresponding dienols.
Catalytic reduction of nitro aromatic compounds with hydrogen sulfide and carbon monoxide
-
, (2008/06/13)
In the reduction of di- or polynitro aromatic compounds by gaseous H2 S over a solid catalyst, addition of CO gas promotes formation of amino groups from all nitro groups in the molecule. A preferred embodiment is reduction of 2,4- and/or 2,6-dinitrotoluene in vapor phase at 325° C. over a supported iron or supported cobalt catalyst on a support comprising alumina. The amino products are useful for production of polyurethane resins.
