Cyclohexane-1, 2-dicarboxylic anhydrid

Apart from the alkenyl succinic anhydrides, other cyclic anhydrides are solids, requiring the use of a delivery solvent, or a solid-state reaction. Apart from succinic anhydride, phthalic (PA) (Figure 4.2a) (Risi and Arseneau, 1958) and maleic anhydride (MA) have also been extensively studied (Figure 4.2b) (Clemons etal., 1992). Goethals and Stevens (1994) have reported reaction of wood with glutaric (Figure 4.2c) or cyclohexane-1,2-dicarboxylic anhydride (Figure 4.2d) and subsequent reaction with epichlorohydrin. 

Figure 4.2 Structures of phthalic (a), maleic (b), glutaric (c), cyclohexane-1,2-dicarboxylic anhydride (d)...

Selective bromine-fluorine exchange of one bromine atom occurs in the reaction of tram-4,5-dibromo-m-cyclohexane-1.2-dicarboxylic anhydride (10) with sulfur tetrafluoride to give isomers of 5-bromo-l,l,3.3,7-pentafluoro-c/.v-octahydroisobenzofuran (11) and 4-bromo-5-fluoro-m-1.2-bis(trifluoromethyl)cyclohexane (12) in a 5 1 ratio and good total yield.11... 

Araldite HT 907 Cyclohexane-1,2-dicarboxylic anhydride EINECS 201-604-9 Hexahydrophthalic acid anhydride Hexabydrophthalic anhydride HHPA Lekutherm Hardener H NSC 8622 NT 907. Widely used as an epoxy hardener. It may also be used in the manufacture of alkyd resins, plasticizers, and polyesters. Crystals mp = 32 bpi 8 = 145. Buffalo Color Corp. 

Synonyms 1,2-Cyclohexanedicarboxylic anhydride Cyclohexane-1,2-dicarboxylic anhydride HHPA Empirical CsHioOs Formula C6Hio(CO)20... 

In contrast to the alkaloid derived catalyst, some work groups focused their attention on synthetic amino alcohols as desymmetrization catalyst. In 2001, Uozomi et al, reported a series of A -chiral bicyclic tertiary amines 77 for the methanolysis of cyclohexane-1,2-dicarboxylic anhydride [83, 84]. In the presence of a stoichiometric amount of catalyst 77, the desymmetrization of the anhydride proceeds with up to 89% ee (Scheme 7.16). 

Suitable cyclic carboxylic anhydrides for this process are for example cz5-l,2-cyclohexane-dicarboxylic anhydride (HHPA), cz5-l,2-cyclohex-4-ene-dicarbo-xylic anhydride (THPA), phthalic anhydride (PA), succinic anhydride (SA), 1-oct-2-ene-succinic anhydride (OSA), and glutaric anhydride (GA) - see Fig. 9. 

Reiznautt QB, Garcia ITS, Samios D. Oligoesters and polyesters produced by the curing of sunflower oil epoxidized biodiesel with cis-cyclohexane dicarboxylic anhydride synthesis and characterization. Mater Sci Eng C 2009 29 2302-2311. 

Oligoester Reaction product of 1,4-butanediol diglycidyl ether, 2-ethyl-1, 3-hexanediol, and 4-methy1-1,2-cyclohexane dicarboxylic acid anhydride MW 830 f = 4 r - 0.75. 

Scheme 2, The modification of acrylated epoxidized soybean oil (AESO) shown using cyclohexane dicarboxylic anhydrade or maleic anhydride. These AESOs were cured with styrene or other comonomers (20).

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%. 

The experiment that follows involves the conversion of 4-cyclohexene-cis-1,2-dicarboxylic acid (3) to cyclohexane-cis-l,2-dicarboxylic acid (4), as shown in Equation 17.8. The catalytic hydrogenation of 3 is considered to be selective because the carboxylic acid groups, -CO2H, are not reduced under the reaction conditions. The starting material for this reduction may be readily prepared by the hydrolysis of 4-cyclohexene-czs-l,2-dicarboxylic acid anhydride, which is the product of the Diels-Alder reaction between butadiene and maleic anhydride, according to the procedure outlined in Section 12.3, Part Cl. 

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