Fumarate, dimethyl

Donor substituents on the vinyl group further enhance reactivity towards electrophilic dienophiles. Equations 8.6 and 8.7 illustrate the use of such functionalized vinylpyrroles in indole synthesis[2,3]. In both of these examples, the use of acetyleneic dienophiles leads to fully aromatic products. Evidently this must occur as the result of oxidation by atmospheric oxygen. With vinylpyrrole 8.6A, adducts were also isolated from dienophiles such as methyl acrylate, dimethyl maleate, dimethyl fumarate, acrolein, acrylonitrile, maleic anhydride, W-methylmaleimide and naphthoquinone. These tetrahydroindole adducts could be aromatized with DDQ, although the overall yields were modest[3]. 

Hydroformylation. Esters of maleate and fumarate are treated with carbon monoxide and hydrogen in the presence of appropriate catalysts to give formyl derivatives. Dimethyl fumarate [624-49-7] is hydroformylated in 1 1 CO/H2 at 100°C and 11.6 MPa pressure with a cobalt [7440-48-4] catalyst to give an 83% yield of dimethyl formylsuccinate [58026-12-3] product (72). 

In a manner analogous to classic nitrile iinines, the additions of trifluoro-methylacetonitrile phenylimine occur regiospecifically with activated terminal alkenes but less selectively with alkynes [39], The nitnle imine reacts with both dimethyl fumarate and dimethyl maleate m moderate yields to give exclusively the trans product, presumably via epimenzation of the labile H at position 4 [40] (equation 42) The nitrile imine exhibits exo selectivities in its reactions with norbornene and norbornadiene, which are similar to those seen for the nitrile oxide [37], and even greater reactivity with enolates than that of the nitnle oxide [38, 41], Reactions of trifluoroacetomtrile phenyl imine with isocyanates, isothiocyanates, and carbodiimides are also reported [42]... 

Diels and Meyer found that the exothermic reaction obtained on dropping pyridine into dimethyl acetylenedicarboxylate in methanol gave a mixture of the indolizine (108) and a methoxymethylindolizine formulated as (109), and some dimethyl fumarate and dimethyl methoxyfumarate. Later workers - obtained only the methoxymethylindolizine in rather poor yield. The indolizine (108) has also been isolated from the products obtained when the addition reaction was carried out in ether, but in this case the course of the reaction was very susceptible to the presence of impurities in the ether, and the results indicated that ethanol was necessary as a reactant. ... 

Hydrogenation of the acridone over Raney nickel gave acridone itself and dimethyl fumarate. 

The imine (161), obtained from 1-aminopyridinium iodide and potassium carbonate, combines with dimethyl acetylenedicarboxylate yielding in the first place (162) which then with more ester gives dimethyl fumarate and the pyrazolopyridine (163), isolated in 15% yield. A corresponding reaction with isoquinoline imine gave 75% of the primary adduct [(cf. (162)]. ... 

Anthracene, dimethyl fumarate, and aluminum chloride give the adduct in 2 hours. When 2 molar equivalents of aluminum chloride are used, the reaction is complete in 5 minutes. The product is recrystallized from methanol, mp 108-109°. 

Irradiation of 5-acetyldibenz[i>,/]azepine (19) in the presence of. V-methylmaleimide results in a mixture of the homo dimer 20 and the mixed dimer 21. No [2 + 2] cycloadducts are obtained, however, with other alkenes such as styrene, acetylenedicarboxylic acid, dimethyl fumarate or acrylonitrile.32 Later studies have demonstrated that the dimerization occurs via the excited triplet state.196... 

Charlton121 has recently reported the asymmetric induction in the reaction of dimethyl fumarate and l,3-dihydrobenzo[c]thiophene 2,2-dioxide (198) containing a chiral a-alkoxy group at the 2-position (equation 128). A diastereomeric excess of 2.8 1 of 199 to 200 is achieved by using 198 derived from optically active a-methylbenzyl alcohol. 

Hexanediol (0.5 mol/L), dimethyl fumarate (0.5 mol/L), toluene and Novozyme (33.3 g/L) are introduced in a thermostatted double-jacketted reactor fitted with a short thermostatted distillation column and a nitrogen inlet. The temperature is set at 60°C and a nitrogen flow (0.2 L/min) is bubbled into reaction medium. Methanol and toluene are collected in a flask and die volume of the solution is held constant by addition of toluene. After reaction (15 days) the catalyst is removed by filtration and the solvent is evaporated under reduced... 

Note Polyfhexamethylene maleate) can be synthesized according to the same procedure using dimethyl maleate instead of dimethyl fumarate. In this case, a mixture of linear chain (76% mass) and cychc species (24% mass) are obtained. 

The discovery that Lewis acids can promote Diels-Alder reactions has become a powerful tool in synthetic organic chemistry. Yates and Eaton [4] first reported the remarkable acceleration of the reactions of anthracene with maleic anhydride, 1,4-benzoquinone and dimethyl fumarate catalyzed by aluminum chloride. The presence of the Lewis-acid catalyst allows the cycloadditions to be carried out under mild conditions, reactions with low reactive dienes and dienophiles are made possible, and the stereoselectivity, regioselectivity and site selectivity of the cycloaddition reaction can be modified [5]. Consequently, increasing attention has been given to these catalysts in order to develop new regio- and stereoselective synthetic routes based on the Diels-Alder reaction. 

Diels-Alder reactions are stereospecific with respect to the E- and Z-relationships in both the dienophile and the diene. For example, addition of dimethyl fumarate and dimethyl maleate with cyclopentadiene is completely stereospecific with respect to the cis or trans orientation of the ester substituents. 

Other a,0-unsaturated carbonyl and acid derivatives, such as dimethyl-fumarate, 2,5-dimethylquinone, and Pmy-cinnamic acid, are known to dimerize in the crystalline state and will be discussed in Section 10.4. 

Dimethyl fumarate (DMF) is used by producers as a biocide to kill moulds that may cause furniture or shoe leather to deteriorate during storage and transportation in a humid climate. Placed in sachets, which are fixed inside the furniture or added to the footwear boxes, DMF evaporates and impregnates the leather, protecting it from moulds. However, it has been found to seriously affect consumers who were in contact with the products. DMF penetrated through the clothes onto the skin of many consumers. Cases of severe health problems have been reported in UK, Finland, France and Poland. Although it is normally not used by tanneries, there are examples where tanneries have used DMF. 

The polymerization of dimethyl maleate and 1,6-hexanediol proceeded using lipase CA catalyst in toluene to give the polymer exhibiting exclusively cis structure [55]. During the polymerization, cyclic oligomers were formed. The cycles were semi-crystalline, whereas the linear polymer was amorphous. In the lipase CA-catalyzed copolymerization of dimethyl maleate and dimethyl fumarate with 1,6-hexanediol, the content of the cyclization was found to depend mainly on the configuration and concentration of the monomers [56]. 

Degradation of 49 at 0°C in a HCl-saturated toluene solution gave Cp2TiCl2 in quantitative yield and dimethyl succinate in 60% yield. Air oxidation at 0°C of a toluene solution of 49 yielded dimethyl fumarate quantitatively. 

---