Itaconic acid methyl ester

When assessing catalytic results reported for new ligands, one must bear in mind that their quality and relevance differ widely. For most new ligands only experiments with selected model test substrates carried out under standard conditions are available, and very few have already been applied to industrially relevant problems. The test substrates for alkenes used most frequently are Aceta-mido Cinnamic Acid (ACA) or its methyl ester (MAC), Methyl Acetamido Acrylate (MAA), ITaconic Acid or DiMethyl ITaconate (ITA, DMIT) and selected aryl enamides (Fig. 25.3). 

In asymmetric hydrogenation of olefins, the overwhelming majority of the papers and patents deal with hydrogenation of enamides or other appropriately substituted prochiral olefins. The reason is very simple hydrogenation of olefins with no coordination ability other than provided by the C=C double bond, usually gives racemic products. This is a common observation both in non-aqueous and aqueous systems. The most frequently used substrates are shown in Scheme 3.6. These are the same compounds which are used for similar studies in organic solvents salts and esters of Z-a-acetamido-cinnamic, a-acetamidoacrylic and itaconic (methylenesuccinic) acids, and related prochiral substrates. The free acids and the methyl esters usually show appreciable solubility in water only at higher temperatures, while in most cases the alkali metal salts are well soluble. 

In addition to the above-mentioned monomers, various acrylic and methacrylic esters, methacrylonitrile, itaconic acid, crotonic acid, methyl vinyl ketone, allyl alcohol, allyl amine etc., have been studied by Fischer... 

Polyitaconic add is converted completdy to the methyl ester with diazomethane (7), while Fisher esterification results in partial esterification of both itaconic acid homo- and copolymers (6). DMI homopolymers and its copolymer with butadiene can be reduced with lithium aluminum hydride to the polymeric alcohols, which on the basis of solubility, may under some conditions be partially cross-linked by intermolecular ester formation (6). Hydrazine converts polydimethyl itaccmate to the polymeric dihydrazide which is water-soluble and exhibits reducing properties. The hydrazide can be treated with aldehyde or ketones to form polymeric hydrazones (45). A cross-linked polymer of bi chloroethyl ita-conate) on treatment with trietlylamine, has been converted by partial quatemization to an anion exchange resin (46). 

If an analogy with methacrylate is valid, one expects the n-butyl ester of itaconic acid to be less sensitive than the methyl ester. Reported values for poly(n-butyl methacrylate) are about half those for PMMA (9). In the present work, PDnBI indeed shows little advantage over PMMA (Figure 3). The ratio of G(s) for the n-butyl ester of itaconic acid to that for the methyl ester was found to be approximately the same as the ratio reported for the corresponding methacrylate esters. 

Stepwise substitution in the phenyl rings of phosphines such as BDPP creates new diastereomeric pairs due to chirality on phosphorus. In a detailed investigation into the hydrogenation of (Z)-a-acetamidocinnamic acid, its methyl ester and dimethyl itaconate, the catalyst was prepared from [Rh(cod)Cl]2 plus 2 equiv. of (2S,4S)-BDPP or its mono-, di-, tri-, or tetrasulfonated derivative (25-28) [93],... 

Yazdani-Redram, M. Vega, H. Quijada, R. Melt functionahzation of polypropylene with methyl esters of itaconic acid. Polymer 2001,42, 4751-4758. 

Poly(itaconic acid) has also been prepared in a 0.2M/liter aqueous solution using potassium persulfate at 50 C over a 5-hr period under reduced pressure. After the polymer is reprecipitated twice into methanol-ethyl acetate, a polymer is isolated with a molecular weight of 1.64 x 10, determined by vapor pressure osmometry of a methanolic solution of the methyl ester prepared from the polymer [49]. Unfortunately Tsuchida and coworkers did not report on the quantitative extent to which poly(methyl itaconate) had been formed from this polymer (presumably by reaction with diazomethane). Consequently, there is little in the literature to confirm or dispute the paper by Braun and Azis el Sayed [97], which offered evidence that during the free-radical polymerization of itaconic acid, carbon dioxide evolves to a considerable extent. During the process, it seems that hydroxyl and formyl radicals are generated and incorporated in the macromolecule. It is proposed by these authors that the homopolymer of itaconic acid contains virtually no itaconic acid repeat units but rather intramolecular lactone rings and acetal- or hemiacetal-like moieties. Since the polymer remains soluble in the reaction solvent (dioxane). 

Water is the ideal solvent from the cost and pollution viewpoints, but it is a non-solvent for many surface coating polymers. It will ssolve a small number of homopolymers, notably those derived from acrylamide, acrylic acid, itaconic acid, vinyl methyl ether, vinyl pyrrolidone and vinyl sulphonic acid, but none of these homopolymers forms flexible films of use in the coatings industry. While copolymers of acrylic or methacrylic acids with acrylate esters are generally insoluble in water, their salts are soluble when the acid content is over 5% (for hydrophilic monomers) and 12% (for hydrophobic monomers). Such polymers can be prepared in solution, or in emulsion, but not in aqueous solution. This is because the acrylate esters are insoluble in water. The acid is copolymerised in the un-ionised form because the ion is unreactive to free radicals. In emulsion polymerisation, care has to be taken to avoid homopolymerisation of the acrylic or methacrylic acid in the water phase. Suppression of homopolymerisation requires a low concentration of acid throughout the polymerisation process. This can be achieved by using a long reaction period and slow addition of monomer mixture, or by careful pH buffer selection. 

Methylsuccinic acid has been prepared by the pyrolysis of tartaric acid from 1,2-dibromopropane or allyl halides by the action of potassium cyanide followed by hydrolysis by reduction of itaconic, citraconic, and mesaconic acids by hydrolysis of ketovalerolactonecarboxylic acid by decarboxylation of 1,1,2-propane tricarboxylic acid by oxidation of /3-methylcyclo-hexanone by fusion of gamboge with alkali by hydrog. nation and condensation of sodium lactate over nickel oxide from acetoacetic ester by successive alkylation with a methyl halide and a monohaloacetic ester by hydrolysis of oi-methyl-o -oxalosuccinic ester or a-methyl-a -acetosuccinic ester by action of hot, concentrated potassium hydroxide upon methyl-succinaldehyde dioxime from the ammonium salt of a-methyl-butyric acid by oxidation with. hydrogen peroxide from /9-methyllevulinic acid by oxidation with dilute nitric acid or hypobromite from /J-methyladipic acid and from the decomposition products of glyceric acid and pyruvic acid. The method described above is a modification of that of Higginbotham and Lapworth. ... 

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