Maleic acid diethyl ester

Diethyl Maleate Maleic Acid, diethyl ester (8) 2-Butenedioic Acid, diethyl ester (9) (141-05-9)... 

Magnesium, bromo l-(trimethylsilyl)vinyl [49750-22-31,58, 156, 157 Magnesium, methoxy(methyl carbonato-O)- [4861-79-4], 56, 121 Maleic acid, diethyl ester [141-05-9], 58, 80, 82... 

Cassaday (1950), Shostakovski et al. (1951) and Melnikov et al. (1952) investigated extensively the addition reactions of dialkyl phosphorodithioic acids to unsaturated dicarbonic acid esters, and found that the dialkyl phosphorodithioic acids are added at the double bond in the same way as are mercaptans. This reaction was used by Cassaday (1950) who prepared 0,0-dimethyl-S-(l,2-dicarbethoxy)-ethyl phosphorodithioate by the addition reaction of dimethyl phosphorodithioic acid and maleic acid diethyl ester. This compound, known by the name malathion (89), became one of the most important phosphorus ester insecticides because of its low toxicity to warm-blooded animals. 

The technical production of malathion can be carried out in a single-step process without the intermediate preparation of dimethyl phosphorodithioic acid, starting from phosphorus pentasulfide, methanol and maleic acid diethyl ester (Matolcsy and Oswald, 1955 1957). 

To a suspension of 1.31 g A-acetyl-D,L-alanine (10 mmol) in 10 mL acetic anhydride was added 3.2 mL diethyl acetylenedicarboxylate (20 mmol). The reaction mixture was maintained at 110°C for 2 h, cooled, and then evaporated under reduced pressure. The oily residue was dissolved in hot cyclohexane and left in the refrigerator overnight with crystal seeds. Diethyl 2,5-dimethyl pyrrole-3,4-dicarboxylate was isolated as white needles by filtration, in amount of 274 mg, in a yield of 11.4%. The filtrate was evaporated and chromatographed (dry column vacuum chromatography) using CH2CI2 and then CH2Cl2/EtOH (99 1 to 98 2) to afford 1.58 g 2-(2,5-dimethyl-3,4-diethoxycarbonyl)-pyrrolyl maleic acid diethyl ester as a yellowish oil, in a yield of 39%. 

CAS 141-05-9 EINECS/ELINCS 205-451-9 Synonyms (Z)-2-Butenedioic acid diethyl ester EM Ethyl maleate Maleic acid, diethyl ester... 

Maleic acid, diethyl ester. See Diethyl maleate Maleic acid, di-(2-ethylhexyl) ester. See Bis (2-ethylhexyl) maleate... 

C8H11CIO4 chloro-maleic acid diethyl ester 626-10-8... 

Maleimide, N-phenyl. See N-Phenylmaleimide Maleinic acid. See Maleic acid Maleinic resin. See Maleic resin Malenic acid. See Maleic acid N,N-Maleoylhydrazine. See Maleic hydrazide Malic acid (INCI). See N-Hydroxysuccinic acid DL-Malic acid diethyl ester. See Diethyl DL-malate... 

Maleic anhydride see l-Oxacyclopent-3-en-2,5-dione Malonic acid diethyl ester see Diethyl propanedioate MEK see Butan-2-one... 

Ethyl maleate of almost equal purity may be obtained by refluxing a mixture of 29 g. of pure maleic acid, 37 g. (47 ml.) of absolute ethyl alcohol, 95 ml. of sodium-dri benzene and 4 ml. of concentrated sulphuric acid for 12 hours. The ester is isolated as described for Diethyl Adipate (Section 111,100). The yield of diethyl maleate, b.p. 219-220°, is 26 g. 

Feoktistov and coworkers 57) found a third mode of reactivity in a closely related system. The electrochemical reduction of the diethyl esters of dichloro-maleic (56) and dichlorofumaric (57) acid was studied. Neither afforded the corresponding acetylene. 

R) - and (S)-l-phenylethylamine to the diethyl esters of fumaric and maleic acid which are carried out by heating the pure compounds, without solvent, to 115-120 °C for three days (see Table 1). The reaction mixtures are then hydrolyzed and hydrogenated to give aspartic acids in high yields (85-87%) but very low optical purities (6.3-12.2%). A number of intermediates and by-products arc isolated, especially amides and imides of the dicarboxylic acids participating in the reaction. This may explain the low overall diastereoselectivity which can be calculated from the low optical rotation of the isolated aspartic acids. However, any discussion of the reaction mechanism remains difficult because the structures of the substrates and products of the actual addition step itself are not known with certainty. It is known that... 

By retro synthetic analysis collagenase inhibitor RO0319790 (1) can be assembled from two chiral building blocks, (R) -succinate 2 and (S)-tert-leucine N-methyla-mide 13. As the latter can be prepared from commercially available (S)-tert-leucine 8 our work concentrated in particular on the construction of the first building block 2. In order to assemble the carbon skeleton of 2 in the most efficient way, extremely cheap maleic anhydride 4 was converted in a known ene reaction with isobutylene to provide the cyclic anhydride 6. Hydrogenation of the double bond followed by the addition of EtOH/p-TsOH yielded the racemic diethyl ester substrate 9 for the enzyme reaction. The enzymatic monohydrolysis of 9 afforded the monoacid (R)-2a. (R)-2 a was coupled via its acid chloride with leucine amide 13 to ester 14, which finally was converted into the hydroxamic acid 1. 

A mixture of calendic acid methyl ester 1 (3 mmol, 1.50 g) and maleic anhydride (5 mmol, 0.49 g) was heated for 2h at 150 °C under nitrogen. The reaction was followed by thin-layer chromatography [petroleum ether-diethyl ether (7 3), Rf 1=0.60, Rf 3=0.23], Purification of product 3 was achieved by column chromatography [silica gel using petroleum ether/diethyl ether (7 3) and petroleum ether/ethyl acetate (1 1) as eluent]. Fractions containing product 3 were collected and the solvent was removed in vacuo. Compound 3 was recrystallized from petroleum ether/diethyl ether (4 1). 

The esters of maleic acid can be hydroformylated to obtain the formyl derivative 8. Adkins and Kresk reported the reaction of diethyl fumerate 7. In the presence of a cobalt catalyst at 150°C and a total pressure of 4 800 psi of carbon monoxide and hydrogen (2 1) CO Hi, the Oxo product, diethyl formylsuccinate 8 (R = Et), was formed in a 51% yield. The fate of the remaining material was not specified but it is believed to have mostly converted to diethyl succinate by hydrogenation (see below). 

Addition of bromine has been the subject of a number of studies. When a neutral salt of maleic or fumaric acid (A = COO ) is brominated in water, the meso derivative is the predominant product. Bell and Pring also report that the meso product is obtained on bromination of the diethyl esters of fumaric and maleic acids. Terry and Eicheberger observed 78% meso product from disodium maleate, a cis addition product which is unexpected. The prevalent bromonium ion mechanism proposed by Roberts and Kim-ball could easily explain the trans addition as follows ... 

F. Wachholtz, Z. Phys. Chem. 125, 1 (1927) (transformation of diethyl ester of fiimaric acid into the ester of maleic acid) same journal 135,147 (1928) (transformation of maleic into liunaric acid). 

Maleate esters such as dimethyl maleate, diethyl maleate and dibutyl maleate are extensively used in the production of latex emulsion polymers, thermoplastic and thermosetting plastics. Dimethyl maleate has found use in applications where improvement in hardness and toughness of polymer films are desired. This includes, in particular, the improvement of anti-blocking properties of copolymers of vinyl acetate with dimethyl maleate. It is also used as an internal modifier to increase the glass transition temperature of styrene or vinyl chloride polymer. The intermediate in esterification of maleic acid with methanol, monomethyl maleate provides plastsizing effect, as well as promotion of improved polymer adhesion due to the carboxylic group. It can be copolymerized with a variety of vinyl and acrylic monomers to provide coatings with improved stiffness and adhesion and reduced tackiness or tendency to block. Monoesters of maleates are used to provide carboxylic acid functionality in emulsions and water-soluble polymers. 

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