Fumaric diethyl ester

The Diels-Alder reaction between fumaric diethyl ester and anthracene can be done in 30 minutes at 250°C with microwave radiation, whereas its conventional counterpart in p-xylene requires several hours. See Figure 12.25. 

Diethyl fumarate Fumaric acid, diethyl ester (8) 2-Butenedioic acid ( )-, diethyl ester (9) (623-91-6)... 

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... 

Condensations of chloroacetyl chloride (and similar compounds) with substituted ethylenediamines to give 1,4-disubstituted piperazin-2-ones have been described, and a number of 4-alkyl(or aralkyl)- -arylpiperazin-2-ones has been prepared either by catalytic debenzylation or pyrolytic debenzylation (or demethylation) of I,l-dialkyl(or l,l-diaralkyl)-3-oxo-4-arylpiperazinium halides (1609). 3-Ethoxy-carbonylmethylene-6-methylpiperazin-2-one has been synthesized by the reaction of diethyl acetylenedicarboxylate with propylenediamine (1610), and treatment of diethyl fumarate with propylenediamine has been shown to give 3-ethoxycarbonyl-methyl-6-methylpiperazin-2-one, also prepared from the diethyl ester of N- 2 -hydroxyiminopropyl)aspartic acid (84) (1611). 

If the diethyl esters, instead of dimethyl fumarate or maleate, are used with 3,3-dimcthoxycy-dopropene, there is no codimerization at temperatures below 60 C. At 90-110°C, the reaction can be forced to proceed but, even in the absence of catalyst, a thermal cycloaddition occurs. The ortho ester 25b is formed as the result of a thermal degradation of the primary adduct. Methanol formed during the degradation process is trapped by unchanged primary product 23b. Additional side products are also formed in the reaction. 

Diethyl fumarate Butenedioic acid-(E) diethyl ester... 

Beilstein Handbook Reference) AI3-05613 Anti-Psoriaticum BRN 0775347 2-Butenedioic acid (E)-, diethyl ester 2-Butenedioic acid (2E)-, diethyl ester 2-Butenedioic acid, diethyl ester, (E)- trans-2-Butenedioic acid diethyl ester Diethyl fumarate Diethylester kyseliny fumarove EINECS 210-819-7 Fumaric acid, diethyl ester HSDB 5722 NSC 20954. Uquid mp = 0.8" bp = 214° d = 1.0452 Am" 213 nm (MeOH) insoluble in H2O, soluble in Me2CO, CHCI3. 

Ethoxy-4-methyloxaole has been used to form pyridoxine (MI-286, R = H). With maleic anhydride it gives an adduct that, on treatment with ethanolic hydrogen chloride, forms the products W-287 and XII-288 (R = R - Et) and a monoester (XII-288 R = Et, R = H or R = H, R = Et). The diethyl ester MI-288 is also formed from ethyl maleate or ethyl fumarate and 5-ethoxy-4-methyloxazole. Fumaronitrile and ethoxy-4inethyloxazol ve 4,5-dicyano-2-methyl-3-pyridinol, ° also a known precursor to pyridoxine. 5-Ethoxy 4-irethyloxaolesand 2-butene-1,4-diol give pyridoxine (XII-286, R = H), which is difficult to purify when prepared in this way (assay, 23%). 

Occasionally, a contaminant in unsaturated polyester resins due to the reaction between free fumaric acid and ethanol. Sometimes occurs as contaminant in the insecticide Malathion Synonyms ethyl fumarate 2-butenedioic acid (E) diethyl ester... 

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 ... 

C2H2(COOC2Hs)2 (tram), fumaric acid, diethyl ester CH CH2 CHa... 

A limitation of external plasticizers of this kind is that they may eventually be lost by evaporation or by migration into the substrate, leaving an imperfect and brittle film. This limitation may be overcome by the use of copolymers and these are now widely used in surface coatings and other applications. Comonomers which may be employed for this purpose include butyl acrylate, 2-ethylhexyl acrylate, diethyl fumarate, diethyl maleate and vinyl esters of fatty acids (e.g. a branched Cio fatty acid). Typically, the copolymers contain 15-20% by weight of such comonomers. These copolymers are readily prepared by the emulsion polymerization techniques described previously for the homopolymer. 

Poly(diethyl fumarate) 2698-06-6 2-Butenedioic acid (E>, diethyl ester, homopolymer R (C8H,204). 

Elving and co-workers [39, 40] investigated the polarographic behavior of mono- anddibromosubstituted maleic andfumaric acids and their esters. Monobromomaleic acid is reduced to maleic, fumaric, and butadiene-1,2,3,4-tetracarboxylic acid, where the proportions of the products depend on the pH value. Monobromofumaric acid is reduced to fumaric acid. The esters of both acids are reduced to the esters of unsubstituted fumaric acid. Dibromomaleic and dibromofumaric acids and their esters are reduced to acetylene-dicarboxylic acid, and the half-wave potentials of the cis acid and its diethyl ester are less negative (by 0.04-0.18 and 0.10-0.12 V, respectively, depending on the pH value) than the half-wave potentials of the trans compounds. 

C8H11CIO4 chloro-fumaric acid diethyl ester 10302-94-0... 

Chromium (II) sulfate is capable of reducing a variety of functional groups under mild conditions 10). Of particular interest is its ability to reduce a,jS-unsaturated esters, acids, and nitriles to the corresponding saturated compounds. This capability is illustrated in the procedure by the reduction of diethyl fumarate. 

Surprisingly, the 7t-system geometry in a substrate has a notable influence in the enzymatic aminolysis of esters. The reaction of diethyl fumarate with different amines or ammonia in the presence of CALB led to the corresponding trans-amidoesters with good isolated yields, but in the absence of enzyme, a high percentage of the corresponding Michael adduct is obtained (Scheme 7.9). Enzymatic aminolysis of diethyl maleate led to the recovery of the same a, P-unsaturated amidoester, diethyl fumarate, and diethyl maleate. The explanation of these results can be rationalized via a previous Michael/retro-Michael type isomerization of diethyl maleate to fumarate, before the enzymatic reaction takes place. In conclusion, diethylmaleate is not an adequate substrate for this enzymatic aminolysis reaction [23]. 

PPF catalyzed an enantioselective polymerization of bis(2,2,2-trichloroethyl) tra 5-3,4-epoxyadipate with 1,4-butanediol in diethyl ether to give a highly optically active polyester (Scheme 9). °° The molar ratio of the diester to the diol was adjusted to 2 1 to produce the (-) polymer with enantiomeric purity of >96%. The polymerization of racemic bis(2-chloroethyl) 2,5-dibromoadipate with excess of 1,6-hexanediol using lipase A catalyst produced optically active trimer and pentamer. The polycondensation of 1,4-cyclohexanedimethanol with fumarate esters using PPL catalyst afforded moderate diastereoselectivity for the cis/trans monocondensate and markedly increased diastereoselectivity for the dicondensate product. 

The common by-products obtained in the transition-metal catalyzed reactions are the formal carbene dimers, diethyl maleate and diethyl fumarate. In accordance with the assumption that they owe their formation to the competition of olefin and excess diazo ester for an intermediate metal carbene, they can be widely suppressed by keeping the actual concentration of diazo compound as low as possible. Usually, one attempts to verify this condition by slow addition of the diazo compound to an excess (usually five- to tenfold) of olefin. This means that the addition rate will be crucial for the yields of cyclopropanes and carbene dimers. For example, Rh6(CO)16-catalyzed cyclopropanation of -butyl vinyl ether with ethyl diazoacetate proceeds in 69% yield when EDA is added during 30 minutes, but it increases to 87 % for a 6 h period. For styrene, the same differences were observed 65). 

Diethyl fumarate and diethyl maleate reacted with the allenic ester to yield trans-and cis-265, respectively, as the single product. 

Chromium(II) sulfate is a versatile reagent for the mild reduction of a variety of bonds. Thus aqueous dimethylformamide solutions of this reagent at room temperature couple benzylic halides, reduce aliphatic monohalides to alkanes, convert vicinal dihalides to olefins, convert geminal halides to carben-oids, reduce acetylenes to /raw5-olefins, and reduce a,j3-unsatu-rated esters, acids, and nitriles to the corresponding saturated derivatives. These conditions also reduce aldehydes to alcohols. The reduction of diethyl fumarate described in this preparation illustrates the mildness of the reaction conditions for the reduction of acetylenes and o ,j8-unsaturated esters, acids, and nitriles. 

A-Phenylthiomethylpipecolic acid methyl ester afforded with methyl cin-namate and a mixture of two regioisomers 65 and 66 (84TL1579). Pipecolic acid and diethyl fumarate or maleinate gave three isomers (85TL2775). 

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