Butadiene-1-carboxylic acid

Although this idea is not without merit, it is not the whole explanation— butadiene-1-carboxylic acid 2 142 and acrylic acid 2.143 also give mainly the ortho adduct 2.144. Since butadiene-1-carboxylic acid can be expected to have a partial positive charge on C-4 (2.141, arrows), that atom ought to be repelled by the partial positive charge on the (J carbon of the acrylic acid. A better explanation for the regioselectivity will be given on p. 54 in Chapter 3. 

Another example, in which the simple curly arrow argument would not have predicted the right answer, is the reaction of butadiene-1-carboxylic acid (213) and acrylic acid (214). Both adducts (215 and 216) are formed, but the... 

Fig. 4-48 Frontier orbitals for Diels-Alder reaction between butadiene-1 carboxylic acid and acrylic acid...

Butadiene-1-carboxylic acid and styrene, Y. A. Titov and A. I. Kuznetsova, Izvest. Akad. Nauk SSSR, Otdel. Khim. Nauk, 1960, 1810 and 1815 Chem. Abs., 1961, 55, 15408c and 15408f) H. R. Snyder and G. I. Poos, J. Am. Chem. Soc., 1949, 71, 1057 2-cyanolbutadiene dimerising (which is also a Z-substituted dienophile), C. S. Marvel and... 

Asymmetric induction to main-chain chiral centers can also be achieved by the radical polymerization of sorbates having chiral ester groups [80,81] and 1,3-butadiene-1-carboxylic acid complexed with optically active amines [82,83],... 

For example, it would not work in the case of the reaction between butadiene carboxylic acid 6.208 and acrylic acid 6.209. The curly arrows 6.207 establish that C-4 of the diene carboxylic acid can be expected to be electrophilic, just like C-3 of the acrylic acid. The partial positive charges ought to repel each other and the adduct expected would be the meta adduct 6.211. In contrast, the reaction gives mainly the ortho adduct 6.210.777... 

An example of an asymmetric induction from optically inactive monomers in an anionic polymerization of esters of butadiene carboxylic acids with (/ )-2-methylbutyllithium or with butyllithium complexed with (-)-menthyl ethyl ether as the catalyst. The products, tritactic polymers, exhibit small, but measurable, optical rotations. Also, when benzofiiran, that exhibits no optical activity, is polymerized by cationic catalysts like aluminum chloride complexed with an optically active cocatalyst, like phenylalanine, an optically active polymer is obtained. ... 

The room temperature isomerization of the vinyl lactones (17), which are readily prepared by addition of keten to the appropriate aldehyde, into the corresponding butadiene carboxylic acid (18) is catalysed by Pd(OAc)2 aptotic solvents. Yields are in the range 50—80%, and the rate of reaction can be increased by addition of tertiary phosphines or phosphites. With saturated lactones, however, polymerization is the main pathway. In protic solvents (MeOH, EtOH) ring-opening takes place to give the ether acid (19) in reasonable yield. 

Carboxylic acids react with butadiene as alkali metal carboxylates. A mixture of isomeric 1- and 3-acetoxyoctadienes (39 and 40) is formed by the reaction of acetic acid[13]. The reaction is very slow in acetic acid alone. It is accelerated by forming acetate by the addition of a base[40]. Addition of an equal amount of triethylamine achieved complete conversion at 80 C after 2 h. AcONa or AcOK also can be used as a base. Trimethylolpropane phosphite (TMPP) completely eliminates the formation of 1,3,7-octatriene, and the acetoxyocta-dienes 39 and 40 are obtained in 81% and 9% yields by using N.N.N M -tetramethyl-l,3-diaminobutane at 50 in a 2 h reaction. These two isomers undergo Pd-catalyzed allylic rearrangement with each other. 

Butadiene—Methacrylic Acid Ionomers. Carboxyl groups can readily be introduced into butadiene elastomers by copolymerization, and the effects of partial neutralization have been reported (63—66). The ionized polymers exhibit some degree of fluidity at elevated temperatures, but are not thermoplastic elastomers, and are very deficient in key elastomer properties such as compression set resistance. 

Ebdon and coworkers22 "232 have reported telechelic synthesis by a process that involves copolymerizing butadiene or acetylene derivatives to form polymers with internal unsaturation. Ozonolysis of these polymers yields di-end functional polymers. The a,o>dicarboxy1ic acid telechelic was prepared from poly(S-s tot-B) (Scheme 7.19). Precautions were necessary to stop degradation of the PS chains during ozonolysis. 28 The presence of pendant carboxylic acid groups, formed by ozonolysis of 1,2-diene units, was not reported. 

Chromium, (ri6-benzene)tricarbonyl-stereochemistry nomenclature, 1,131 Chromium complexes, 3,699-948 acetylacetone complex formation, 2,386 exchange reactions, 2,380 amidines, 2,276 bridging ligands, 2,198 chelating ligands, 2,203 anionic oxo halides, 3,944 applications, 6,1014 azo dyes, 6,41 biological effects, 3,947 carbamic acid, 2,450 paddlewheel structure, 2, 451 carboxylic acids, 2,438 trinuclear, 2, 441 carcinogenicity, 3, 947 corroles, 2, 874 crystal structures, 3, 702 cyanides, 3, 703 1,4-diaza-1,3-butadiene, 2,209 1,3-diketones... 

Carboxylic acids, a-bromination of 55, 31 CARBOXYLIC ACID CHLORIDES, ketones from, 55, 122 CARBYLAMINE REACTION, 55, 96 Ceric ammonium nitrate [Ammonium hexa mtrocerate(IV)[, 55, 43 Chlorine, 55, 33, 35, 63 CHROMIUM TRIOXIDE-PYRIDINE COMPLEX, preparation in situ, 55, 84 Cinnamomtnle, a-phenyl- [2-Propeneni-tnle 2,3-diphenyl-], 55, 92 Copper(l) iodide, 55, 105, 123, 124 Copper thiophenoxide [Benzenethiol, copper(I) salt], 55, 123 CYCLIZATION, free radical, 55, 57 CYCLOBUTADIENE, 55, 43 Cyclobutadieneiron tricarbonyl [Iron, tn-carbonyl(r)4-l,3-cyclo-butadiene)-], 55,43... 

Pastor-Sempere N., Eemandez-Garcfa J.C., Orgiles-Barcelo A.C., Pastor-Bias M.M., Martfn-Martfnez J.M., and Dillard J.G., 1998, Surface treatment of styrene-butadiene rubber with carboxylic acid, in First International Congress on Adhesion Science and Technology, W.J. van Ooij and H.R. Anderson Jr. (Eds), Utrecht, VSP, 461 94. 

Isomerization has been observed with many a,j3-unsaturated carboxylic acids such as w-cinnamic 10), angelic, maleic, and itaconic acids (94). The possibility of catalyzing the interconversion of, for example, 2-ethyl-butadiene and 3-methylpenta-l,3-diene has not apparently been explored. The cobalt cyanide hydride will also catalyze the isomerization of epoxides to ketones (even terminal epoxides give ketones, not aldehydes) as well as their reduction to alcohols. Since the yield of ketone increases with pH, it was suggested that reduction involved reaction with the hydride [Co" (CN)jH] and isomerization reaction with [Co (CN)j] 103). A related reaction is the decomposition of 2-bromoethanol to acetaldehyde... 

We found that completely soluble compounds can be obtained in two ways. The first method, which is widely applicable, is to react a rare earth carboxylate with a small amount of an aluminum alkyl (11). Neodymium octoate can be converted into a product which is completely soluble in cyclohexane by reacting one mole of it with 1 to 5 moles of triethylaluminum. We also found that the rare earth salts of certain tertiary carboxylic acids are very readily soluble in non-polar solvents (12). In conjunction with a Lewis acid and aluminum alkyls, these compounds form highly active catalysts for the polymerization of butadiene. The neodymium Lewis acid aluminum alkyl molar ratio is within the range 1 (0.4-2.0) (10-40). 

Hydroxycarbonylation and alkoxycarbonylation of alkenes catalyzed by metal catalyst have been studied for the synthesis of acids, esters, and related derivatives. Palladium systems in particular have been popular and their use in hydroxycarbonylation and alkoxycarbonylation reactions has been reviewed.625,626 The catalysts were mainly designed for the carbonylation of alkenes in the presence of alcohols in order to prepare carboxylic esters, but they also work well for synthesizing carboxylic acids or anhydrides.137 627 They have also been used as catalysts in many other carbonyl-based processes that are of interest to industry. The hydroxycarbonylation of butadiene, the dicarboxylation of alkenes, the carbonylation of alkenes, the carbonylation of benzyl- and aryl-halide compounds, and oxidative carbonylations have been reviewed.6 8 The Pd-catalyzed hydroxycarbonylation of alkenes has attracted considerable interest in recent years as a way of obtaining carboxylic acids. In general, in acidic media, palladium salts in the presence of mono- or bidentate phosphines afford a mixture of linear and branched acids (see Scheme 9). 

The most characteristic reaction of butadiene catalyzed by palladium catalysts is the dimerization with incorporation of various nucleophiles [Eq. (11)]. The main product of this telomerization reaction is the 8-substituted 1,6-octadiene, 17. Also, 3-substituted 1,7-octadiene, 18, is formed as a minor product. So far, the following nucleophiles are known to react with butadiene to form corresponding telomers water, carboxylic acids, primary and secondary alcohols, phenols, ammonia, primary and secondary amines, enamines, active methylene compounds activated by two electron-attracting groups, and nitroalkanes. Some of these nucleophiles are known to react oxidatively with simple olefins in the presence of Pd2+ salts. Carbon monoxide and hydrosilanes also take part in the telomerization. The telomerization reactions are surveyed based on the classification by the nucleophiles. 

Few studies have been carried out on the telomerization of carboxylic acids other than acetic acid. Carboxylic acids are expected to react similarly with butadiene. The exception is formic acid No telomerization takes place, as described before (33, 34), and it behaves as a reductant rather than a nucleophile, forming 1,6- and 1,7-octadienes and octatriene. 

The reaction of CO2 with 1,3-butadienes in the presence of Ni catalysts usually gave an isomeric mixture of carboxylic acids 89 and 90 after hydrolysis (Scheme 32).47,48 The oxa-7r-allylnickel complexes 87 and 88 might be the reaction intermediates, which could be formed through oxidative cyclization of Ni(0) with C02 and the dienes. When Me2Zn was used as a transmetallation agent to react with the oxa-7r-allylnickel intermediates under a C02 atmosphere, further carboxylation took place at the 7r-allylnickel unit. Thus, the 1,4-diesters 95 were obtained after acidic hydrolysis and treatment with diazomethane as shown in Scheme 32.47... 

Addition reactions, 20 243. See also Electrophilic addition reactions aldehydes, 2 63-64 allyl alcohol, 2 234-239 butadiene, 4 368—370 carboxylic acids, 5 44-45 ethylene, 10 597—598 quinoline, 21 184 quinone, 21 246-261 toluene, 25 165... 

The photolysis of the furan derivatives 78 yielded the butadienals 79 as the main products [123], Further isomerizations leading to allenic esters used the radiation of a cyclopropene-1 -carboxylic acid ester [124] or applied flash vacuum pyrolysis to 3 -ethoxy cyclobut- 2-en-l-one[125]. 

Interesting rearrangements proceed upon refluxing the azido diene 105 in benzene solution and form 61% of the vinylaziridine 106 as a mixture of diastereoisomers and the vinylogous urethane 108 (28%) (equation 37)53. It was shown that the process 106 - 108 occurs entirely at elevated temperature (refluxing xylene, ca 140 °C). However, treatment of the aziridine 106 with p-toluenesulfonic acid in THF at room temperature gives rise to trans,trans-, 3-butadiene carboxylic ester 107 in 98%53. 

The reaction of butadiene with the sulfone of 3-benzo[6]thiophene-carboxylic acid under Diels-Alder conditions gives the adduct (32). Catalytic reduction over platinum oxide removes the 2,3-double bond. 

Styrene-1,3-butadiene copolymers with higher styrene contents (50-70%) are used in latex paints. Styrene and 1,3-butadiene terpolymerized with small amounts of an unsaturated carboxylic acid are used to produce latexes that can be crosslinked through the carboxyl groups. These carboxylated SBR products are used as backing material for carpets. Styrene copolymerized with divinyl benzene yields crosslinked products, which find use in size-exclusion chromatography and as ion-exchange resins (Sec. 9-6). 

Several polymers based on 1,3-dienes are used as elastomers. These include styrene-1,3-butadiene (SBR), styrene-1,3-butadiene terpolymer with an unsaturated carboxylic acid (carboxylated SBR), acrylonitrile-1,3-butadiene (NBR or nitrile rubber) (Secs. 6-8a, 6-8e), isobutylene-isoprene (butyl rubber) (Sec. 5-2i-l), and block copolymers of isoprene or... 

Later, Tieke reported the UV- and y-irradiation polymerization of butadiene derivatives crystallized in perovskite-type layer structures [21,22]. He reported the solid-state polymerization of butadienes containing aminomethyl groups as pendant substituents that form layered perovskite halide salts to yield erythro-diisotactic 1,4-trans polymers. Interestingly, Tieke and his coworker determined the crystal structure of the polymerized compounds of some derivatives by X-ray diffraction [23,24]. From comparative X-ray studies of monomeric and polymeric crystals, a contraction of the lattice constant parallel to the polymer chain direction by approximately 8% is evident. Both the carboxylic acid and aminomethyl substituent groups are in an isotactic arrangement, resulting in diisotactic polymer chains. He also referred to the y-radiation polymerization of molecular crystals of the sorbic acid derivatives with a long alkyl chain as the N-substituent [25]. More recently, Schlitter and Beck reported the solid-state polymerization of lithium sorbate [26]. However, the details of topochemical polymerization of 1,3-diene monomers were not revealed until very recently. 

The telomerization of butadiene by means of water in ILs was described by Dullius et Rottger et al. report a process for the telomerization of acyclic olefins having at least two conjugated double bonds, or their mixtures, using a palladium-carbene complex as catalyst in an IL solvent. The nucleophiles included water, alcohols, phenols, polyols, carboxylic acids, ammonia and primary and secondary amines. The acycylic olefins could be either 1,3-butadiene or isoprene. 

This paper discusses the three butadiene prepolymers which have been used most extensively in solid rocket propellants—i.e., the copolymer of butadiene and acrylic acid (PBAA), the terpolymer of butadiene, acrylic acid, and acrylonitrile (PBAN), and the carboxyl-terminated polybutadiene (CTPB). Since the chemistry of all of these carboxyl-containing prepolymers is essentially the same, the discussion of butadiene propellants in this paper is concerned mainly with those based on CTPB. 

Z. Zhou, N. Liu, and H. Huang, Reactivity of acrylonitrile-butadiene-styrene terpolymer grafted with long-chain unsaturated carboxylic acids, Polymer, 45(21) 7109-7116, September 2004. 

Formaldehyde also reacts with butadiene via the Prins reaction to produce pentenediols or their derivatives. This reaction is catalyzed by a copper-containing catalyst in a carboxylic acid solution (57) or RuC13 (58). The addition of hydrogen also proceeds via 1,2- and 1,4-addition. 

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