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Fumaric acid derivatives Diels—Alder reaction

The synthesis of highly substituted rigid tricyclic nitrogen heterocycles via a tandem four-component condensation (the Ugi reaction)/intramolecular Diels-Alder reaction was investigated in both solution and solid phase [24]. The Ugi reaction in MeOH (Scheme 4.2) involves the condensation of furylaldehydes 17, benzylamine 18, benzyl isocyanide 19 and maleic or fumaric acid derivatives 20, and provides the triene 21 which immediately undergoes an intramolecular Diels-Alder reaction, affording the cycloadduct 22 in a diastereoisomeric mixture with high yield. [Pg.149]

Pyrrolidines and pyrrolidinones can be synthesized on insoluble supports by intramolecular carbometallation of alkenes (Entry 1, Table 15.4) and by Ugi reaction of support-bound isonitriles with amines and 4-oxo acids (Entry 4, Table 15.4). In Entry 5 in Table 15.4, the pyrrolidinone ring is formed by intramolecular Diels-Alder reaction of a furan with a fumaric acid derivative. 2-Pyrrolidinones have also been prepared by treatment of resin-bound O-mesitylenesulfonyl cyclobutanone oximes with... [Pg.392]

Furan [110-00-9] - [BUTADIENE] (Vol 4) - [FURANDERIVATIVES] (Supplement) -from butenediol [ACETYLENE-DERIVED CHEMICALS] (Voll) -Diels-Alder reaction [MALEIC ANHYDRIDE, MALEIC ACID AND FUMARIC ACID] (Vol 15) -from waste combustion [FUELS FROM WASTE] (Vol 12)... [Pg.427]

Narasaka reported a highly enantioselective Diels-Alder reaction between isoprene and a fumaric acid derivative 17 using a catalytic amount of a chiral titanium reagent prepared from tartrate-derived chiral 1,4-diol 18 and TiCI2(0-/-Pr)2 [27]. When a stoichiometric amount of the partially resolved chiral diol (25% ee) was used, the corresponding cycloadduct 19 with 83% ee was obtained (Scheme 9.12). In this reaction, white precipitate was formed, which proved to... [Pg.705]

Fig. 9a4) between cyclopentadiene and a C=C bond of the dumbbell-shaped part of the rotaxane. The dumbbell-shaped part contains two dicarbonyl stations (Fig. 9a3), one derived from fumaric acid (tram -CO-C H=CH-CO-. station 1), the other derived from succinic acid (—CO-CH2-CH2-CO-, station 2). The two diamide sites of the macrocycle can form four H-bonds with the two carbonyl groups of a given station (Fig. 9al for the interaction of the two carbonyl groups of fumaric-acid-derived station 1 with the four NH groups of the macrocycle through four H-bonds, see Fig. 9a2). Station 1 (derived from fumaric acid) has a tram C=C double bond due to its preorganization, this station interacts with the macrocycle better than the station 2. Consequently, the macrocycle is initially located at station 1 (Fig. 9a5). The Diels-Alder cycloaddition (80° C, 90% yield) of cyclopentadiene to the double bond of station 1 results in a mixture of diastereomers (Fig. 9a4) and causes displacement of the macrocycle from station 1 to station 2 (Fig. 9a6). The cycloaddition is reversible and the retro-Diels-Alder reaction occurs quantitatively (250°C, reduced pressure) when cyclopentadiene dissociates from the axle of the rotaxane this produces a displacement of the macrocycle from station 2 back to station 1. [Pg.274]

The oxidation of 1,4-dicarboxylic acids with LTA in benzene results in double decarboxylation with the formation of a double bond (equation 16). Similarly, the pyrolysis of the di-r-butyl peroxy esters of 1,4-dicarboxylic acids in high boiling solvents leads to the formation of double bonds (equation 17). The method is especially useful in so far as 1,4-diacids are readily available from Diels-Alder reactions using derivatives of mtdeic and fumaric acid as the dienophile. Apparently, application of the 0-acyl thiohydroxamate method to 1,4-diacids does not result in the formation of double bonds but rather in the product of double decarboxylative rearrangement (Section S.4.6.1). ... [Pg.722]

A chiral C2-symmetric bridged ferrocene was constructed from a synthetic ligand containing two cyclopentadiene units (Fig. 4-12d). The key step in the synthesis of the ligand is a diastereoselective Diels — Alder reaction of anthracene with bis[(S)-l-ethoxycarbonylethyl]fumarate. When oxidized to the ferrocinium salt, the ferrocene derivative has Lewis acid properties and catalyzes Diels — Alder reactions with some enantioselectivity [85]. [Pg.187]

Unlike lactic acid, mandelic acid (7) occurs in nature only in small amounts and is therefore more expensive. Formerly, it was obtained by resolution of the racemate with a chiral base, such as l-phenylethylamines or ephedrine6, but enantioselective reductions of a-oxo-a-phenylacetic acid by chemical or biochemical methods have become feasible (Section D.2.3.I.). Esters of mandelic acid, e.g.. 8. can be prepared by any convenient esterification technique (see. for example, refs 7 and 46) and have been used for enantioselective protonation reactions (Sections C. and D.2.I.). Similar to the corresponding lactic esters, fumaric acid derivatives 9 are obtained from the mandelic esters and used as chiral dienophiles in diastereoselective Diels Alder reactions (Section D. 1.6.1.1.1.2.2.1.). [Pg.152]

Unmodified rosins combine with fumaric acid and maleic anhydride in accordance with the Diels-Alder reaction to form tribasic adducts. The resulting polybasic acids are often used instead of phthalic anhydride in the production of alkyd resins for low-cost coatings. These rosin-derived, nonphthalate alkyds are used to improve gloss and other properties and are suitable mainly for interior coalings. They do not possess the high degree of outdoor durability characteristic of alkyd resins derived solely from phthalic anhydride. [Pg.376]

Chapuis and Jurczak et al. reported a diastereoselective Diels-Alder reaction of the symmetrical fumaric acid derivatives including a chiral sultam part [15] promoted by Lewis acids, such as SnCU, TiCU(O Pr)4 n, ZrCU, RnAlCU-n, or ZnBr2 [16]. The best result (99% de) was obtained when SnCU or Me2AlCl was used (Scheme 10.2), whereas others except for AlMe3 gave more than 80% de. [Pg.519]

Glovsky et al. observed an anticomplementary activity for levopimaric acid (45), a derivative of abietic acid, and prepared a number of synthetic derivatives such as maleopimaric acid (46) and fumaropimaric acid (47), being Diels-Alder substitution products of levopimaric acid v ith maleic anhydride or fumaric acid, respectively [28, 29]. Maleic acid is cis-butenedioic acid, fumaric acid is trans-butenedioic acid. Maleopimaric acid inhibited complement-mediated haemolysis via classical path-way activation (45% inhibition at a concentration of 500 iM), Fumaropimaic acid inhibited in vivo complement-dependent systemic Frossman, cutaneous Frossman, and reverse passive Arthus reactions. These pimaric acid derivatives have already been included in earlier reviews on complement-active compounds [8, 30]. The... [Pg.150]


See other pages where Fumaric acid derivatives Diels—Alder reaction is mentioned: [Pg.535]    [Pg.170]    [Pg.180]    [Pg.722]    [Pg.271]    [Pg.290]    [Pg.126]    [Pg.155]    [Pg.273]    [Pg.762]    [Pg.80]    [Pg.822]    [Pg.836]    [Pg.371]   
See also in sourсe #XX -- [ Pg.318 ]




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Acids fumar

Diels acid

Diels-Alder reaction acids

Diels—Alder reaction fumarate

Fumarates. Diels-Alder reactions

Fumaric acid

Fumaric acid derivatives

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