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o-Nitrotoluene nitration can produce 2,4-dinitrotoluene and 2,6-dinitrotoluene simultaneously, which is also the common side-reaction of toluene mononitration. Kinetic study is helpful to deepen the understanding of nitration and control the reaction better. A homogeneously continuous microflow system was constructed to determine the kinetic parameters of 2-MNT nitration. A complete kinetic model was established and all kinetic parameters were obtained. In general, the observed reaction rate will increase with increasing H2SO4 mass fraction. However, when the H2SO4 mass fraction increases to a certain value, the observed reaction rate decreases. This is the first time to report the maximum observed reaction rate constant corresponding to the H2SO4 mass fraction at different temperatures in this work. Compared to previous reports on this reaction, the system provides more accurate kinetic parameters and can be developed into a reliable platform for the kinetic study of similar reactions.

The potential energy surfaces (PESs) of three nitrotoluene isomers, such as p-nitrotoluene, m-nitrotoluene, and o-nitrotoluene, have been theoretically built at the CCSD(T)/CBS level. The geometries of reactants, transition states (TSs) and products are optimized at the B3LYP/6-311++G(d,p) level. Results show that reactions of -NO2 isomerizing to ONO, and C-NO2 bond dissociation play important roles among all of the initial channels for p-nitrotoluene and m-nitrotoluene, and that the H atom migration and C-NO2 bond dissociation are dominant reactions for o-nitrotoluene. In addition, there exist pathways for three isomer conversions, but with high energy barriers. Rate constant calculations and branching ratio analyses further demonstrate that the isomerization reactions of O transfer are prominent at low to intermediate temperatures, whereas the direct C-NO2 bond dissociation reactions prevail at high temperatures for p-nitrotoluene and m-nitrotoluene, and that H atom migration is a predominant reaction for o-nitrotoluene, while C-NO2 bond dissociation becomes important by increasing the temperature.

It was shown that a catalyst obtained by depositing palladium nanoparticles from a colloidal solution onto a carbon support stabilized with polyvinylpyrrolidone exhibits higher activity in liquid-phase hydrogenation of o-nitrotoluene than a commercial sample of Pd/C with the same palladium content. From analysis of data from TEM, XRD, and XPS it was concluded that the increase of activity is due to the increased content of Pd0 in the synthesized catalyst.

2-Methyl-4-methoxyaniline (MMA) was synthesized by one-pot method through the hydrogenation and Bamberger rearrangement of o -nitrotoluene in methanol using acidic ionic liquid and 3% Pt/C as catalyst system. The effects of ionic liquid type, dosage of ionic liquid and 3% Pt/C, reaction temperature and reaction pressure on o -nitrotoluene conversion and MMA selectivity were investigated. The results indicated that the imidazolium-based acidic ionic liquid which contains SO 3 H-functionalized cation showed higher selectivity to MMA than other acidic ionic liquids used in this work. Using 1-(propyl-3-sulfonate)-3-methylimidazolium hydrosulfate ([HSO 3 -pmim][HSO 4 ]) as the acid catalyst, the selectivity to MMA was as high as 67.6% at 97.8% of o -nitrotoluene conversion. As 3% Pt/C increased from 0.01 g to 0.025 g, the selectivity to MMA decreased from 73.4% to 62.5%, because of the hydrogenation of intermediate o -methyl-phenylhydroxylamine to o -toluidine becoming more dominant. An increase in hydrogen pressure also had obviously dramatic effect in lowering the MMA selectivity. After easy separation from the products, the catalyst system could be reused at least 3 times.

The promoting effect of ethanol on the synthesis of N -(2-methylphenyl)hydroxylamine from o -nitrotoluene in Zn/H 2 O/CO 2 system was observed. By adding appropriate amount of ethanol, the selectivity of N- (2-methylphenyl)hydroxylamine increased from 71% to 90% when the reduction was carried out at 25 °C under normal pressure of CO 2 .

A density functional theory method, B3LYP/6-31+G(2df,p), has been used to study the secondary processes of the most probable mechanism of gas-phase thermal decomposition of o-nitrotoluene (accompanied with formation of the aci-form at the first stage). The secondary processes of isomerization of aci-nitrotoluene have been recognized as the rate-limiting steps. This is consistent with results of earlier theoretical studies. The results on isomerization of the HONO group in the aci-form of o-nitrotoluene reported herein have substantially corrected the earlier suggested mechanism of thermal degradation of o-nitrotoluene.

Selective oxidation of o-nitrotoluene to o-nitrobenzaldehyde with metalloporphyrins as biomimetic catalysts was studied. The peripheral substituent around porphyrin rings and various process parameters of NaOH concentration, reaction temperature, reaction time and oxygen pressure all affect the selectivity of o-nitrobenzaldehyde. Further, 82.0% selectivity of o-nitrobenzaldehyde was achieved under the optimum conditions: 1.0×10t-5 mol · L−1 of T(p-NO2)PPFeCl catalyst, 2.5 mol · L−1 of NaOH, 0.2 mol · Lt-1 of o-nitrotoluene, 45°C and 2.0 MPa for 6 h.

Heterophase nitration of o-nitrotoluene, in which an increase in the contribution of the reaction in the boundary adsorption monolayer under conditions of surface aeration leads to a higher yield of 2,4-dinitrotoluene and larger 2,4-/2,6-dinitrotoluene isomer ratio, was studied.

The reaction of o-methylphenylnitrene in the presence of alcohol and amine was expected to give isomeric pairs of 3- and 7-methyl-3H-azepine derivatives. The formation ratio between these isomers w...

The reaction of o-methylphenylnitrene in the presence of alcohol (II) and amine (V) is expected to give isomeric pairs of 3-and 7-methyl-3H-azepine derivatives (III)/(IV) and (VI)/(VII).

p53 gene is one of the most frequently mutated genes found in the human colonic tumors. Mice have been used as an experimental model to study the pathogenesis of colon cancer in humans. The alterations in cancer genes and proteins found in the mouse large intestinal tumors included mutations which are hallmarks of human colon cancer, probably contributed to the pathogenesis of the large intestinal carcinomas in mice following o-nitrotoluene (o-nt) exposure. Aim of Study: Detection of p53 gene mutations in colon precancerous stage. Materials and Methods: In this study, mice colon precancerous stage induced by o-nt were examined for the presence of point mutations in highly conserved coding region (exons 5-8) and outside it (exons 10, 11) using a single-strand conformation polymorphism assay (SSCP). Results: SSCP analysis showed no differences in banding patterns between the normal negative control group and o-nt-induced precancerous stage in mice colon. Conclusion: The results from the present study indicate that point mutations in the p53 gene, in the coding region (exons 5-8) and outside it (exons 10, 11), are not involved in the development of the colon precancerous stage induced by o-nt in mice.

The hydrated group 4 metal triflates, Hf(OTf)4 and Zr(OTf)4, were found to be excellent catalysts (10 mol%) for the mononitration of o-nitrotoluene using a single equivalent of concentrated (69%) nitric acid. The only side product is water and the catalysts are readily recycled from the aqueous phase and re-used.

o-Tolidine, obtained by the reduction of o-nitrotoluene, is used in the production of azo-dyestuffs. The electrochemical reduction of nitrotoluene has to take place in two steps. A continuous process is proposed for the first step, i.e., the electrochemical reduction of o-nitrotoluene to o,o-azoxytoluene in an alkaline ethanol-water solution. Azoxytoluene is separated from the catholyte by crystallization and filtration. The solution, obtained after the isolation of azoxytoluene is regenerated by distillation.

The photoelectron photoion coincidence technique has been used to measure the breakdown diagram and the OH loss rates of energy-selected o-nitrotoluene ions. In addition, the subsequent dissociation of C7H6NO+ ions via CO loss which occurs at higher ion internal energies has also been measured. The measured rates are consistent with a mechanism in which the parent o-nitrotoluene ion rearranges to a more stable structure prior to OH loss. This rearranged ion is calculated to be 1.62 eV more stable than the o-nitrotoluene ion and dissociates with an activation energy of 1.5 eV. The heat of formation for the OH loss product, C7H6NO+, is found to be 900 ± 15 kJ mol−1. The results are discussed in light of the earlier photodissociation data of Beynon and co-workers.

2-ニトロトルオール又は2-ニトロエチルベンゾールに醋酸第二水銀を作用せしめる時は3, 4若しくは6の位置に置換せる少くとも3種の化合體が生成する事が明になつた. 2-ニトロトルオールに於てはこの方面の研究は既に二つ知られて居るがそれは互に矛盾せるものなるを以て著者等はここに改めて追試を行ひ一部正誤及び増補を行つたのである.醋酸水銀による置換反應が一般の置換法則に從はないのは興味ある事實である.

Indirect electrochem. oxidn. of o-nitrotoluene to o-nitrobenzaldehyde by Co(III) was studied. The highest aldehyde yield (.apprx.80%) is obtained in dispersing a 70-fold excess of o-nitrotoluene in a soln. of Co2(SO4)3 in 60% H2SO4 at 12 Deg. The influence of acid concn. excess of nitrotoluene and presence of a catalyst are discussed and found to be compatible with a mechanism proposed by C. E. Bawn (1951). [on SciFinder (R)]

A synthesis of 3-hydroxymethyl- and 3-formylindoles has been performed by manipulation of the side chain of 3-hydroxymethylindoline derived from o-nitrotoluene. Electro-reductive cyclization of 2-(2-nitro-phenyl)-1,3-bis(methylsulfonyloxy)propane to 3-(benzyloxymethyl)indole, is also discussed.

A synthesis of 3-hydroxymethyl- and 3-formylindoles has been performed by manipulation of the side chain of 3-hydroxymethylindoline derived from o-nitrotoluene. Electro-reductive cyclization of 2-(2-nitro-phenyl)-1,3-bis(methylsulfonyloxy)propane to 3-(benzyloxymethyl)indole, is also discussed.

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