Dicarboxylic acid esters halides

There are numerous examples of consecutive reactions such as radioactive decay series, hydrolyses of dicarboxylic acid esters or tertiary alkyl halides, as well as nitrations of aromatics. Conversions of gases on catalyst surfaces are also examples of this. 

The benzoic acid derivative 457 is formed by the carbonylation of iodoben-zene in aqueous DMF (1 1) without using a phosphine ligand at room temperature and 1 atm[311]. As optimum conditions for the technical synthesis of the anthranilic acid derivative 458, it has been found that A-acetyl protection, which has a chelating effect, is important[312]. Phase-transfer catalysis is combined with the Pd-catalyzed carbonylation of halides[3l3]. Carbonylation of 1,1-dibromoalkenes in the presence of a phase-transfer catalyst gives the gem-inal dicarboxylic acid 459. Use of a polar solvent is important[314]. Interestingly, addition of trimethylsilyl chloride (2 equiv.) increased yield of the lactone 460 remarkabiy[3l5]. Formate esters as a CO source and NaOR are used for the carbonylation of aryl iodides under a nitrogen atmosphere without using CO[316]. Chlorobenzene coordinated by Cr(CO)j is carbonylated with ethyl formate[3l7]. 

The scope of this reaction is similar to that of 10-21. Though anhydrides are somewhat less reactive than acyl halides, they are often used to prepare carboxylic esters. Acids, Lewis acids, and bases are often used as catalysts—most often, pyridine. Catalysis by pyridine is of the nucleophilic type (see 10-9). 4-(A,A-Dimethylamino)pyridine is a better catalyst than pyridine and can be used in cases where pyridine fails. " Nonbasic catalysts are cobalt(II) chloride " and TaCls—Si02. " Formic anhydride is not a stable compound but esters of formic acid can be prepared by treating alcohols " or phenols " with acetic-formic anhydride. Cyclic anhydrides give monoesterified dicarboxylic acids, for example,... 

Cationic condensation products, namely, the reaction products of a dicarboxylic acid or an ester or acid halide thereof and an aminoalkylamine, that are quatemized are recommended for breaking cmde oil emulsions from fireflooding [365],... 

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). 

Due to reduction or lack of hydrogen bonding, carbonyl carbon nuclei of amides [313-315], anhydrides [316], esters [310-312], and halides [317] display smaller shift values relative to the parent acids (Tables 4.34 and 4.35). Methyl esterification shieldings are about — 6+1 ppm for mono- and — 1.5 + 1 ppm for diesters, reflecting weaker hydrogen bonding in dicarboxylic acids [316] Taking the methoxy carbon as a /i effect... 

Monocationic acyl ions are readily prepared as persistent species in solutions of low nucleophile strength.68 These acyl ions have been thoroughly characterized by IR and NMR spectroscopy, and several acyl ion salts have been characterized by X-ray crystallography. The monocationic acyl ions are often prepared in situ from carboxylic acids, esters, or anhydrides, by the action of a strong Brpnsted acid, or the ions can be prepared from ionization of an appropriate acid halide with a strong Lewis acid. Both methods have been used to prepare acyl-centered dications, some of which can be considered distonic superelectrophiles. As described previously, dicarboxylic acids cleave to the bis-acyl ions in superacid (FSChH-SbFs) provided that the acyl cations are separated by at least three methylene units (eq 54).55 The first bis-acyl dications were reported by Olah and Comisarow, being prepared by the reactions of dicarboxylic acid fluorides with superacidic SbFs (eq 72).69... 

Silver salts of carboxylic acids react with bromine or chlorine in an inert solvent to give carbon dioxide, a silver halide, and the halide containing one less carbon atom than the acid. The method has been reviewed. " Both low- and high-molecular-weight aliphatic bromides have been prepared. "t i i The degradation of silver salts of aromatic acids is complicated by nuclear halogenation." The procedure is valuable as a step in the synthesis of oi-bromo esters (C, to C,) from dicarboxylic acids. ... 

Polymerization reactions involve the union of a number of similar molecules to form a single complex molecule. A polymer is any compound, each molecule of which is formed out of a number of molecules which are all alike, and which are called monomers. In many cases polsonerization can be reversed and the poisoner be resolved to the monomer. Many polymerization reactions which are of industrial importance involve in the initial stages condensations, that is, reactions in which elimination of water or other simple molecules takes place. Compounds which polymerize have some type of unsaturation in the molecule. Olefins, unsaturated halides, esters, aldehydes, dicarboxylic acids, anhydrides, amino acids and amides are among the important groups of compounds which are used in industrial polymerization reactions. The commercial products produced by polymerization reactions may be conveniently classified into (a) resinotds, or synthetic resins (b) elastomers, which possess rubber-like properties and (c) fibroids, used as textile fibers. Two types of resinoids are illustrated in this experiment Bakelite, formed from phenol and formaldehyde, and methacrylate resin formed from an unsaturated ester. 

In principle, what has been said for halogenation of monocarboxylic acids applies also to that of dicarboxylic acids there are preferential -bromination, preferential -chlorination under ionic reaction conditions, decrease in the proportion of a>chloro derivatives in radical chlorination, and in most cases direct or indirect reaction by way of the acid halides. There is, however, the additional complication that two diastereoisomers — the meso- and the racemic form — can usually arise, e.g., with, a/-dihalo dicarboxylic acids and their esters. 

The a>bromo carboxylic acid required for preparation of the a>alkoxy acid is often obtained by a malonic ester synthesis the malonic ester is treated with an alkyl halide, the alkylmalonic acid obtained by hydrolysis of the product is brominated by elemental bromine at a low temperature, and the resulting a>bromo dicarboxylic acid is decarboxylated.54 This has led to a particularly important synthesis of aldehydes which utilizes the decarbonylation of -hydroxy or a-alkoxy acids for conversion of an alkyl halide RX into the aldehyde RCHO containing one more carbon atom ... 

A combination of two of the reactions discussed in this chapter—alkylation of an a-carbon and decarboxylation of a j8-dicarboxylic acid—can be used to prepare carboxylic acids of any desired chain length. The procedure is called the malonic ester synthesis because the starting material for the synthesis is the diethyl ester of malonic acid. The first two carbons of the carboxylic acid come from malonic ester, and the rest of the carboxylic acid comes from the alkyl halide used in the second step of the reaction. 

There are two classical reaction sequences in organic chemistry that rely on enolate alkylation. One is the malonic ester synthesis.61 jjj synthetic example taken from the Clive and Hisaindee synthesis of brevioxime,62 diethyl malonate was treated with a base such as sodium ethoxide, under thermodynamic control conditions. The resulting enolate anion is treated with the indicated alkyl halide to give the alkylated product 81 (in 72% yield).Saponification of 81 to the dicarboxylic acid (82, in 99% yield), was followed by decarboxylation (sec. 2.9.D) and formation of the substituted acid 83, in 94% yield. ... 

Nomenclature for carboxylic acids and dicarboxylic acids. Structure and nomenclature for acid halides, anhydrides, esters, and amides. 

Chapter 16 (Section 16.6) introduced dicarboxylic acids along with their common and lUPAC names. The common names and the lUPAC names are shown again in Table 20.1 for dicarboxylic acids of C2-C10. This chapter deals with the chemistry of carboxylic acids and their derivatives, and dicarboxylic acids have their acyl halide, ester, anhydride, and amide derivatives. The two carboxylic acid units lead to some interesting structural variations, however. 

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