01957nas a2200169   4500008004100000022001400041245011800055210006900173260007100242300001400313490000700327520126300334100001501597700002201612700002101634856013201655       2015                        eng d  a1083-616000aContinuous-flow nitration of o-xylene: effect of nitrating agent and feasibility of tubular reactors for scale-up0 aContinuousflow nitration of oxylene effect of nitrating agent an  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcSEP  a1138-11470 v193 a<p>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.</p>1 aSharma, Y.1 aJoshi, Ramesh, A.1 aKulkarni, A., A.  uhttps://library.ncl.res.in/content/continuous-flow-nitration-o-xylene-effect-nitrating-agent-and-feasibility-tubular-reactors-001160nas a2200145   4500008004100000245009700041210006900138260000800207520060200215100001500817700001500832700002200847700002300869856012200892       2017                        eng d00aContinuous flow telescopic oxidation of alcohols via generation of chlorine and hypochlorite0 aContinuous flow telescopic oxidation of alcohols via generation   cMAR3 aA 3-step continuous flow oxidation of alcohols is demonstrated with continuous generation of chlorine as the first step followed by its use for the flow synthesis of high strength sodium hypochlorite. The solution is subsequently used for oxidation of alcohols in the presence of a catalytic amount of the nitroxyl radical “TEMPO”, which inhibits oxidation at the aldehyde stage. Selective oxidations of eight different alcohols were demonstrated. To achieve identical yields, the aromatic alcohols containing electron withdrawing groups needed a longer residence time than aliphatic alcohols.1 aSharma, Y.1 aMoolya, S.1 aJoshi, Ramesh, A.1 aKulkarni, Amol, A.  uhttps://library.ncl.res.in/content/continuous-flow-telescopic-oxidation-alcohols-generation-chlorine-and-hypochlorite01306nas a2200145   4500008004100000245009200041210006900133260000800202300001700210520075800227100001500985700001801000700002101018856012101039       2019                        eng d00aTelescoped sequence of exothermic and endothermic reactions in multistep flow synthesis0 aTelescoped sequence of exothermic and endothermic reactions in m  cJAN  aArticle ASAP3 aA multistep sequential flow synthesis of isopropyl phenol is demonstrated, involving 4-step exothermic, endothermic, and temperature sensitive reactions such as nitration, reduction, diazotization, and high temperature hydrolysis. Nitration of cumene with fuming nitric acid produces 2- and 4-nitrocumene which are converted into respective cumidines by the hydrogenation using Pd/Ni catalyst in H-cube with gravity separation. Hydrolysis of in situ generated diazonium salts in the boiling acidic conditions is carried out using integration of flow and microwave-assisted synthesis. 58% of 4-isopropyl phenol was obtained. The sequential flow synthesis can be applied to synthesize other organic compounds involving this specific sequence of reactions.1 aSharma, Y.1 aNikam, A., V.1 aKulkarni, A., A.  uhttps://library.ncl.res.in/content/telescoped-sequence-exothermic-and-endothermic-reactions-multistep-flow-synthesis