Dicarboxylic acid esters double

Besides nickel and cobalt, almost all of the catalysts discussed in the last chapter which were suited for the formation of free acids can be applied, e. g. rhodium, palladium and, with certain restrictions, iron. Cobalt hydrocarbonyl catalyzes the stoichiometric ester synthesis at mild reaction conditions [35, 121]. The initially formed acylcobalt carbonyls react rapidly with alcohols even at 50 °C and, in the presence of Na-alcoholate, even at 0 °C to give esters [121]. Dienes with isolated double bonds react with carbon monoxide and alcohols at mild reaction conditions in the presence of Pd/HCl to give unsaturated monocarboxylic acid esters and at more severe conditions to give saturated dicarboxylic acid esters [508]. 

This reaction provides a useful way of introducing a double bond next to a carbonyl group. Here it is in a synthesis by Barry Trost of the Queen Bee Substance (the compound fed by the workers to those bee larvae destined to become queens). The compound is also a pheromone of the termite and is used to trap these destructive pests. Trost started with the monoester of a dicarboxylic acid, which he converted to a methyl ketone by reacting the acyl chloride with a cuprate. The ketone was then protected as a dioxolane derivative to prevent it enolizing, and the sulfur was introduced by reacting the enolate of the ester with the sulfur electrophile MeSSMe. 

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... 

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). ... 

The application of the procedure to azides containing other functional groups has also been described. Diamines (from dicarboxylic acids), arylha loamines, and nitroarylamines have been successfully prepared, whereas certain groups like the double bond, hydroxyl, carbonyl, and amino often cause the formation of products other than the anticipated amine. For the synthesis of a-amino acids, the readily accessible alkylcyanoacetic esters may be employed as starting materials. Their azides rearrange to cyano isocyanates, which can be easily hydrolyzed. ... 

Af-Unsubstituted pyrazoles and indazoles add to compounds containing activated double and triple bonds (67HC 22)1,B-76MI40402>. Amongst C—C double and triple bonds, maleic anhydride, acrylic acid esters and nitriles, acetylene-carboxylic and -dicarboxylic esters (78AHC(23)263), quinones, and some a,/3-unsaturated ketones have been used with success. Phenylacetylene reacts with pyrazole in the presence of Na/HMPT as catalyst to yield the Z isomer of 1-styrylpyrazole in a highly stereoselective reaction (78JHC1543). 

This co-unsaturated ester is an excellent substrate for a number of important polymers It can be converted into a Cn-dicarboxylic acid, which can be utilized for the manufadure of polyesters, or into 10-aminodecanoic add, which leads to nylon 10. The epoxidation of the terminal double bond provides 9,10-epoxydecanoic acid, which can be used for the production of epoxy resins. 

For example, malonic esters can be made by PTC carbonylation of ethyl chloroa-cetate at 1 bar CO at 25 °C in the presence of cobalt carbonyl. Ni(CN)2 was used for the PTC double carbonylation of alkynols, using PEG-400 as the phase-transfer catalyst, LaCls as an additional co-catalyst, toluene as the solvent, and 0.5 M NaOH as the optimum base concentration. Yields of ene-dicarboxylic acids were up to 97%. 

Won et al. [19], have reported synthesis of polyesters with valine, leucine, isoleucine, methionine, and phenylalanine (Table 12.1). This three-step process involves synthesis of a diester and a dinitro compound that are copolymerized [19], An amino acid is first coupled with a diol (with 3, 4, or 6 methylene groups) in the presence of tosyl to yield a diester with acid salts of diamine at the terminal ends. The second monomer, di-p-nitrophenyl ester of carboxylic acids, is synthesized by a condensation reaction of adipoyl or se-bacoyl chloride with p-nitro phenol. The final polymerization step involves an arduous condensation reaction in the presence of a strong proton abstractor between acid salt of bis(amino acid-alkyne diester) and di-p-nitrophenyl ester of dicarboxylic acids. Following along the same lines, Chu and Guo [22] have copolymerized a mixture of nitro phenyl ester of succinate, adipate, or sebacate and nitrophenyl fumarate with toluenesulfonic acid salt of phenylalanine butane-1,4-diester. The addition of fumarate derivative to the monomer mixture provides an unsaturated double bond in the polymer backbone that can be functionalized for specific biomedical... 

Bbcin the monomethyl ester of the C24 dicarboxylic acid, norbixin. Norbixin has 4 methyl side branches, 2 terminal carboxyl groups and 9 conjugated double bonds. Ihe C20 chain corresponds to the middle part of P-carotene. In naturally occurring B. (m.p. 198 C) the A double bond is cis, but it easily isomerlzes to form the more stable all-trans B. (m. p. 217 °C). B. is a diapocarotenoid formed by oxidation of a C40 carotenoid. It is a yellow to red-orange pigment found in the seeds of Bixa orellana, from which it is extracted for use as a food colorant. 

Hyperflorin, an antibiotic isolated from St. John s wort Hypericum perforatum L.), has been found on the basis of chemical and spectroscopic evidence to possess structure (639). ° A review on the conformational analysis of bicyclo[3,3,l]nonanes has appeared,and the conformations of l,5-disubstituted-3,7-dimethyIenebicyclo-[3,3,l]nonane derivatives have been shown, on the basis of lanthanide-induced n.m.r. shifts, to be predominantly in the double-chair form. In a notable paper that contains a wealth of information pertinent to adamantane synthesis, it has been reported that bicyclo[3,3,l]nonane-3,7-dicarboxylic acid, its dimethyl ester, and various derivatives exist mainly in the chair-boat conformation. The synthetic entry to these systems is illustrated for the above diester (643) in which the starting point is adamantanone (640) thus, ring expansion with diazomethane followed by SeOj oxidation gave the a-diketone (641) which was cleaved with periodate to give the diacid (642). Esterification using diazomethane gave (643) which exists, as does the diacid, as... 

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