Dimethyl adipate, oxidation

Following hydrogenation over palladium on carbon(33), dimethyl adipate hydrolysis to adipic acid is carried out using a strong mineral acid such as sulfuric acid. Hydrolysis is nearly quantitative with a selectivity of 99.5%. Since the adipic acid from the oxycarbonylation process contains no branched by-product acids, as is the case with the commercial oxidation process, extensive recrystallization is not required to produce a polymer grade material. Results indicate that the dried adipic acid crystals contain less than. 5 weight % moisture and are 99.95 weight % pure on a dry basis. 

Oxidation. Oxidation of methoxycyclopropanol (1) with cupric nitrate proceeds via the methyl jS-propionatc radical (2) to give methyl acrylate (3) and dimethyl adipate (4). Ferric nitrate, Fe(N03)3, can also be used. 

An oxy radical of related type may be involved in the oxidation by ceric ion of the hemiacetal (29) of cyclopropanone. Although the spectrum of the radical (30) has not been observed, that of its open-chain isomer (31) has been identified using a flow technique. This mechanism may account for the oxidation of (29) with silver or cupric ion to dimethyl adipate, by dimerization of (31) (Schaafsma et al., 1966). 

Methyl acrylate can be dimerized to give a molecule that can be hydrogenated to dimethyl adipate the latter, in turn, can be hydrolyzed to yield AA. Methyl acrylate is synthesized by esterification of acrylic acid, which is obtained by the two-step oxidation of propylene. However, the overall scheme requires several reaction steps, and investment requirements may be large. 

DBDPO. See Decabromodiphenyl oxide DBE. See Ethylene dibromide DBE-4. See Dimethyl succinate DBE-5. See Dimethyl glutarate DBE-6. See Dimethyl adipate DBE-224, DBE-621, DBE-712, DBE-814, DBE-821. See Dimethylsiloxane/EO copolymer DBE-C25. See EO/dimethylsiloxane/EO block copolymer... 

Decylamine oxide Dicocodimethylamine dimerate Dihexyl adipate Diisodecyl adipate Diisostearyl fumarate Dilinoleic acid Dimethyl adipate Dimethyl succinate Dioctyl adipate Dioctyl sebacate... 

S, styrene DVB, divinyl benzene EVD, ethyl vinyl benzene CAN, acrylonitrile DPPO, 2,6-diphenyl-p-phenyl oxide PVP, polyvinyl pyridine EGDMA, ethylene glycol dimethyl adipate NP, nonpolar MP, medium polar SP, strongly polar. 

The addition of various Kolbe radicals generated from acetic acid, monochloro-acetic acid, trichloroacetic acid, oxalic acid, methyl adipate and methyl glutarate to acceptors such as ethylene, propylene, fluoroolefins and dimethyl maleate is reported in ref. [213]. Also the influence of reaction conditions (current density, olefin-type, olefin concentration) on the product yield and product ratios is individually discussed therein. The mechanism of the addition to ethylene is deduced from the results of adsorption and rotating ring disc studies. The findings demonstrate that the Kolbe radicals react in the surface layer with adsorbed ethylene [229]. In the oxidation of acetate in the presence of 1-octene at platinum and graphite anodes, products that originate from intermediate radicals and cations are observed [230]. 

Process Economics Program Report SRI International. Menlo Park, CA, Isocyanates IE, Propylene Oxide 2E, Vinyl Chloride 5D, Terephthalic Acid and Dimethyl Terephthalate 9E, Phenol 22C, Xylene Separation 25C, BTX, Aromatics 30A, o-Xylene 34 A, m-Xylene 25 A, p-Xylene 93-3-4, Ethylbenzene/Styrene 33C, Phthalic Anhydride 34B, Glycerine and Intermediates 58, Aniline and Derivatives 76C, Bisphenol A and Phosgene 81, C1 Chlorinated Hydrocarbons 126, Chlorinated Solvent 48, Chlorofluorocarbon Alternatives 201, Reforming for BTX 129, Aromatics Processes 182 A, Propylene Oxide Derivatives 198, Acetaldehyde 24 A2, 91-1-3, Acetic Acid 37 B, Acetylene 16A, Adipic Acid 3 B, Ammonia 44 A, Caprolactam 7 C, Carbon Disulfide 171 A, Cumene 92-3-4, 22 B, 219, MDA 1 D, Ethanol 53 A, 85-2-4, Ethylene Dichloride/Vinyl Chloride 5 C, Formaldehyde 23 A, Hexamethylenediamine (HMDA) 31 B, Hydrogen Cyanide 76-3-4, Maleic Anhydride 46 C, Methane (Natural Gas) 191, Synthesis Gas 146, 148, 191 A, Methanol 148, 43 B, 93-2-2, Methyl Methacrylate 11 D, Nylon 6-41 B, Nylon 6,6-54 B, Ethylene/Propylene 29 A, Urea 56 A, Vinyl Acetate 15 A. 

Triphenylbismuth carbonate (2) displays remarkable chemoselecdvity, aUowing alcohol oxidation in the presence of benzenethiol, pyrrolidine, indole, aniline, dimethyl aniline and 3-pyrolidinocholesta-3,S-diene. The diol moiety in (3) is cleaved selectively without oxidizing the dithioacetal function (equation 3). The rate of the stoichiometric oxidative cleavage of ciJ-cyclohexane-l,2-diol to adipic aldehyde with Ph3BiC03 is faster than that of the trans isomer, suggesting the formation of a cyclic organobismuth intermediate (4 Scheme 1). ... 

ADIPIC ACID, DIMETHYL ESTER (627-93-0) Combustible liquid (flash point 225°F/ I07 C cc). Incompatible with strong acids, nitrates, oxidizers. 

Ans TerephthaUc acid and ethylene glycol (or dimethyl terephthalate) for PET, cyclohexanone oxime or caprolactam for nylon 6, adipic acid and hexamethylene diamine for nylon 6,6, and lactide for polylactide, respectively. (a) Unlike PET, polylactide is a biodegradable material (b) nitrous oxide is a greenhouse gas and an ozone depleter, and as it cannot be recycled, its removal is essential (c) conventional bleaching produces... 

An analysis of the overall crystallization rate with composition requires that the comparison be made either at constant undercooling or at one of the nucleation temperature quantities, T / T AT or T /T(AT). This requirement is essential because of the importance of nucleation to the crystallization process. The overall crystallization kinetics of a variety of polymer-diluent systems have been reported. Many different relations between the overall crystallization rate and composition have been observed. For example, as is shown in Fig. 13.17 there is a continuous decrease in the crystallization rate with dilution for linear polyethylene-a-chloronaphthalene mixtures.(42) The results for poly(trans-1,4-isoprene) in methyl oleate follow a similar pattem.(80) In contrast, the rates for poly(dimethyl siloxane) crystallizing from toluene, at compositions V2 = 0.32 to 0.79, are the same at all undercoolings, but are faster than that of the pure polymer.(78) Another example is found with poly(ethylene oxide)-diphenyl ether mixtures.(77) In this case the crystallization rates for the pure polymer and composition = 0.92 to 0.51 are the same. However, the rates for the more dilute mixtures, V2 = 0.04 and 0.30 are lower. For poly(decamethylene adipate)-dimethyl formamide mixture the rates for the pure polymer and V2 = 0.80 are the same.(77) The mixture of isotactic poly(propylene) with dotricontane shows interesting behavior.(81) At all undercoolings studied, the crystallization rate initially decreases with dilution, reaches a minimum in the range V2 — 0.7 (a maximum in ti/2) and then slowly increases with further dilution, up to V2 = 0.10. 

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