Xi:Irritant;
117-84-0Relevant articles and documents
Mechanisms of Heptane Degradation and Product Formation in Microwave Discharge
Bobkova,Stokolos,Garifullin
, p. 336 - 340 (2019/08/15)
Abstract: A mechanism for the degradation of n-heptane and the formation of the products of its plasma-chemical transformation by microwave discharge treatment has been proposed. Chemical reactions resulting in reactive species, namely free radicals that form lower hydrocarbons and polyaromatic structures are presented. The product composition of the gas, liquid, and solid phases has been studied using gas chromatography–mass spectrometry analysis of the precipitate obtained by evaporation of the liquid phase after the treatment of n-heptane.
Solvent-free facile synthesis of di-octyl phthalate over heterogeneous sulfated zirconia acid catalyst
Parmar, Ajay M,Saravanan,Tyagi, Beena,Srinivasan, Kannan
, p. 747 - 755 (2017/08/04)
The present study reports the synthesis of di-octyl phthalate (DOP), widely used as a plasticizer, via solvent-free esterification of phthalic acid and n-octanol over sulfated zirconia (SZr) heterogeneous acid catalyst. A comparison with other heterogeneous acid catalysts such as K-10 acid activated clay, zeolites (β and Y), Amberlyst-15 resin shows the superior activity of SZr, exhibiting maximum conversion of n-octanol (88%) with 93% DOP selectivity at 160 °C in 6 h. The rate of the reaction for SZr catalyst is computed as 17.3 mmol h?1 g?1. The catalyst activity is stable upon recycling for up to five cycles. The weak acid sites of the catalyst are postulated as the responsible active centres involved in the reaction. The reaction has been successfully scaled up over twenty five times; and the product DOP (67 g, 99% by GC) isolated and characterized by FT-IR and 1H NMR spectroscopy. It is noteworthy that the activity of SZr catalyst is comparable with that of H2SO4 and p-toluene sulphonic acid (p-TSA), which clearly suggets its potential as an efficient alternative to conventional commercial homogeneous acid catalysts for the synthesis of DOP.
An esterification and purifying and cleaning production process (by machine translation)
-
Paragraph 0018; 0019; 0020; 0021; 0023; 0024; 0025-0031, (2017/05/23)
The invention relates to a production process of esterification purifying and cleaning. The invention using nano solid acid catalyst to catalyze the esterification reaction in order to improve the reaction activity, and membrane separation technology follow-up of the refining process, including washing and water washing, catalyst separation and decompression dealcoholization. The refining process to realize the whole process continuous, automatic operation, high production efficiency, product quality is stable. The catalyst separation process with the esterification reaction process in a system coupled to the same, the fine suspended state and the catalyst in the separation and recovery process the loss in serious problems. Membrane separation of low energy consumption, octanol high recovery efficiency. (by machine translation)
NOVEL SINGLE STEP ESTERIFICATION PROCESS OF ALDEHYDES USING A HETEROGENEOUS CATALYST
-
Page/Page column 20, (2016/06/20)
The present invention relates to a novel simple, efficient and single-step process for esterification of aldehydes using a heterogeneous catalyst with high yields. More particularly, the present invention relates to a novel simple, efficient and single-step process for esterification of aldehydes using Titanium superoxide with greater than 80% yields.
Titanium superoxide-a stable recyclable heterogeneous catalyst for oxidative esterification of aldehydes with alkylarenes or alcohols using TBHP as an oxidant
Dey, Soumen,Gadakh, Sunita K.,Sudalai
, p. 10631 - 10640 (2015/11/17)
Titanium superoxide efficiently catalysed the oxidative esterification of aldehydes with alkylarenes or alcohols, under truly heterogeneous conditions, to afford the corresponding benzyl and alkyl esters in excellent yields. Mechanistic studies have established that this "one pot" direct oxidative esterification process proceeds through a radical pathway, proven by a FTIR spectral study of a titanium superoxide-aldehyde complex as well as spin trapping experiments with TEMPO. The intramolecular version of this protocol has been successfully demonstrated in the concise synthesis of 3-butylphthalide, an anti-convulsant drug.
Sulfonated graphene as highly efficient and reusable acid carbocatalyst for the synthesis of ester plasticizers
Garg, Bhaskar,Bisht, Tanuja,Ling, Yong-Chien
, p. 57297 - 57307 (2015/02/02)
Plasticizers are well known for their effectiveness in producing flexible plastics. The automotive, plastic and pharmaceutical industries, essential to a healthy economy, rely heavily on plasticizers to produce everything from construction materials to medical devices, cosmetics, children toys, food wraps, adhesives, paints, and 'wonder drugs'. Although H2SO4 is commonly used as commodity catalyst for plasticizer synthesis it is energy-inefficient, non-recyclable, and requires tedious separation from the homogeneous reaction mixture resulting in abundant non-recyclable acid waste. In this study, for the first time, we report an efficient synthesis of ester plasticizers (>90% yields) using sulfonated graphene (GSO3H) as an energy-efficient, water tolerant, reusable and highly active solid acid carbocatalyst. The hydrothermal sulfonation of reduced graphene oxide with fuming H2SO4 at 120°C for 3 days afforded GSO3H with remarkable acid activity as demonstrated by 31P magic-angle spinning (MAS) NMR spectroscopy. The superior catalytic performance of GSO3H over traditional homogeneous acids, Amberlyst-15, and acidic ionic liquids has been attributed to the presence of highly acidic and stable sulfonic acid groups within the two dimensional graphene domain, which synergistically work for high mass transfer in the reaction. Furthermore, the preliminary experimental results indicate that GSO3H is quite effective as a catalyst in the esterification of oleic and salicylic acid and thus may pave the way for its broad industrial applications in the near future.
Efficient synthesis of symmetrical phthalate and maleate diesters using phosphinite ionic liquids
Valizadeh,Khalili
, p. 529 - 534 (2013/02/22)
Symmetrical dialkyl phthalates and maleates were synthesized using phosphinite ionic liquid as a catalyst and reaction medium. The results indicated that phosphinite ionic liquid shows better catalytic and reusable performance without using any acid or base catalyst. Under the optimum conditions, using 1-methyl-3-(4-phosphinitebutyl) imidazolium chloride as catalyst, the conversion of phthalic and maleic anhydrides to the corresponding diesters of primary and secondary alcohols was occurred in 72-85% yields. The diesters of tertiary alcohols and phenols could not be prepared by this method. A kind of widely used plasticizer, dioctyl phthalate, was prepared in good yield under these conditions. The ionic liquid could be reused three times after easy separation from the products without any disposal. Iranian Chemical Society 2012.
SO42-/SnO2: Efficient, chemoselective, and reusable catalyst for acylation of alcohols, phenols, and amines at room temperature
Satam, Jitendra R.,Gawande, Manoj B.,Deshpande, Sameer S.,Jayaram, Radha V.
, p. 3011 - 3020 (2008/02/12)
SO42-/SnO2 was employed for the acylation of a variety of alcohols, phenols, and amines under solvent-free conditions at room temperature. This method showed preferential selectivity for acetylation of the amino group in the presence of a hydroxyl group. The reported method is simple, mild, and environmentally viable, using several other acid anhydrides at room temperature. Copyright Taylor & Francis Group, LLC.
Process for producing carboxylic acid esters and catalysts therefor
-
, (2008/06/13)
A process for producing carboxylic acid esters by the following steps: a) preparation of a reaction mixture containing an alcohol and a carboxylic acid and/or a carboxylic anhydride and/or a carboxylic acid ester and or a partially esterified carboxylic acid, b) heating of this mixture to the suitable reaction temperature in the presence of a solid polysiloxane insoluble in the reaction medium and having sulphonic acid groups with intensive thorough mixing accompanied by continuous separation of the reaction water which forms, wherein the polysiloxane used as the catalyst in modified by treatment with a soluble aluminum, titanium or zirconium compound, and the spherical particles thereof have a diameter of 0.01 to 3 mm, a specific surface of 0.1 to 1200 m2 /g, a specific pore volume of 0.01 to 6.0 ml/g and a bulk density of 50 to 1000 g/l.
