Salts carboxylate

A special application of the Japp-Klingemann/Eischer sequence is in the preparation of tryptamines from piperidone-3-carboxylate salts, a method which was originally developed by Abramovitch and Shapiro[2]. When the piperidone is subjected to Japp-Klingemann coupling under mildly alkaline conditions decarboxylation occurs and a 3-hydrazonopiperidin-2-one is isolated. Fischer cyclization then gives 1-oxotetrahydro-p-carbolines which can be hydrolysed and decarboxylated to afford the desired tryptamine. 

Methyl ketones are cleaved on re action with excess halogen in the presence of base The products are a trihalomethane (haloform) and a carboxylate salt... 

To isolate the carboxylic acid a separate acidification step following hydrolysis is nec essary Acidification converts the carboxylate salt to the free acid... 

Amides are sometimes prepared directly from carboxylic acids and amines by a two step process The first step is an acid-base reaction m which the acid and the amine combine to form an ammonium carboxylate salt On heating the ammonium carboxy late salt loses water to form an amide... 

Aldonic acids exist m equilibrium with their five or six membered lactones They can be isolated as carboxylate salts of their open chain forms on treatment with base... 

Methyl group (Section 2 7) The group —CH3 Mevalonic acid (Section 26 10) An intermediate in the biosyn thesis of steroids from acetyl coenzyme A Micelle (Section 19 5) A sphencal aggregate of species such as carboxylate salts of fatty acids that contain a lipophilic end and a hydrophilic end Micelles containing 50-100 car boxylate salts of fatty acids are soaps Michael addition (Sections 18 13 and 21 9) The conjugate ad dition of a carbanion (usually an enolate) to an a 3 unsatu rated carbonyl compound... 

Saponification (Section 20 11) Hydrolysis of esters in basic solution The products are an alcohol and a carboxylate salt The term means soap making and denves from the process whereby animal fats were converted to soap by heating with wood ashes... 

In addition to providing fully alkyl/aryl-substituted polyphosphasenes, the versatility of the process in Figure 2 has allowed the preparation of various functionalized polymers and copolymers. Thus the monomer (10) can be derivatized via deprotonation—substitution, when a P-methyl (or P—CH2—) group is present, to provide new phosphoranimines some of which, in turn, serve as precursors to new polymers (64). In the same vein, polymers containing a P—CH group, for example, poly(methylphenylphosphazene), can also be derivatized by deprotonation—substitution reactions without chain scission. This has produced a number of functionalized polymers (64,71—73), including water-soluble carboxylate salts (11), as well as graft copolymers with styrene (74) and with dimethylsiloxane (12) (75). 

Color intensity and permanence are improved by metal carboxylate salts, especially 2inc salts (83), which cataly2e the dye development and stabili2e the dye in its colored form. The substituted novolak resin, along with extender and binder, can be apphed to the receiving sheet as a solution or aqueous dispersion. Aqueous dispersions are probably the most widely used they are manufactured by the resin suppher or the user from the base resin. 

Most commercial sorbic acid is produced by a modification of this route. Catalysts composed of metals (2inc, cadmium, nickel, copper, manganese, and cobalt), metal oxides, or carboxylate salts of bivalent transition metals (2inc isovalerate) produce a condensation adduct with ketene and crotonaldehyde (22—24), which has been identified as (5). 

Oil Repellent. Fluorochemicals are the only class of material that can provide oil repeUency without altering the porosity of the paper or paperboard. Physical barriers to oil penetration are used primarily for their moisture- or gas-barrier properties, with retarded oil penetration as a secondary benefit. The most common od-repeUent additives are long-chain perfluoroalkyl phosphate salts of ammonia or diethanol amine. Commercial sources include Scotchban (3M), Zonyl (DuPont), and Lodyne (Ciba Specialties). There are also a fluorochemical carboxylate salt, Lodyne (Ciba Specialties), and fluorochemical copolymers, eg, Scotchban (3M). The widest range of oily fluid holdout is provided by the fluorochemical copolymers. 

Alkyds. Alkyd resins (qv) are polyesters formed by the reaction of polybasic acids, unsaturated fatty acids, and polyhydric alcohols (see Alcohols, POLYHYDRic). Modified alkyds are made when epoxy, sUicone, urethane, or vinyl resins take part in this reaction. The resins cross-link by reaction with oxygen in the air, and carboxylate salts of cobalt, chromium, manganese, zinc, or zirconium are included in the formulation to catalyze drying. 

It should be noted that when 3-acylisoxazoles (116) are heated with a base such as sodium ethoxide, the acyl group is eliminated to give a carboxylate salt and a /3-ketonitrile (117). The reaction probably occurs via initial attack at the carbonyl group (46G206). 

The reaction of 2,4-diphenylisoxazolin-5-one with amines produced malondiamide and a ketenamine intermediate was suggested (70TL4473, 73DIS(B)1434). Stronger bases gave similar products and amine salts and malonimide intermediates were postulated to be involved in the reaction (76JA6036). The use of A/-t-butyl-4-phenylisoxazolin-5-one produced an insoluble ketenamine carboxylate salt which on protonation produced a malonimide (Scheme 67) (77H(7)247). 

Low surface energy substrates, such as polyethylene or polypropylene, are generally difficult to bond with adhesives. However, cyanoacrylate-based adhesives can be effectively utilized to bond polyolefins with the use of the proper primer/activa-tor on the surface. Primer materials include tertiary aliphatic and aromatic amines, trialkyl ammonium carboxylate salts, tetraalkyl ammonium salts, phosphines, and organometallic compounds, which are initiators for alkyl cyanoacrylate polymerization [33-36]. The primer is applied as a dilute solution to the polyolefin surface, solvent is allowed to evaporate, and the specimens are assembled with a small amount of the adhesive. With the use of primers, adhesive strength can be so strong that substrate failure occurs during the course of the shear tests, as shown in Fig. 11. 

The pyrolysis of perfluoro carboxylic salts can result both in mono and bimolecular products At 210-220 °C, silver salts give mostly the coupled products, at 160-165 °C in A -methylpyrrolidinone, the corresponding copper salts also give the simple decarboxylated compounds in nearly equal amounts The decomposition of the copper salts m the presence of lodobenzene at 105-125 °C results m a phenyl derivative, in addition to the olefin and coupled product [94] (equations 60-62)... 

Micelle (Section 19.5) A spherical aggregate of species such as carboxylate salts of fatty acids that contain a lipophilic end and a hydrophilic end. Micelles containing 50-100 carboxylate salts of fatty acids are soaps. 

Reactant and product structures. Because the transition state stmcture is normally different from but intermediate to those of the initial and final states, it is evident that the stmctures of the reactants and products should be known. One should, however, be aware of a possible source of misinterpretation. Suppose the products generated in the reaction of kinetic interest undergo conversion, on a time scale fast relative to the experimental manipulations, to thermodynamically more stable substances then the observed products will not be the actual products of the reaction. In this case the products are said to be under thermodynamic control rather than kinetic control. A possible example has been given in the earlier description of the reaction of hydroxide ion with ester, when it seems likely that the products are the carboxylic acid and the alkoxide ion, which, however, are transformed in accordance with the relative acidities of carboxylic acids and alcohols into the isolated products of carboxylate salt and alcohol. 

The synthesis of flavones has also seen modifications over the years. One of the primary modifications has been substituting the carboxylate salt for other bases. Kohn and Low showed that catalytic amounts of triethylamine allowed for the reaction to be run at 160 Looker and coworkers expanded on the Kohn and Low modification by using amines as the solvent, and thus reduced the reaction temperatures. They typically found that the reaction could be run at the refluxing temperatures of the amine. They showcased this modification by converting oi-methoxyphloroacetophenone (35) to the methyl ether of galangin (36) using a variety of amines in 60-75% yield with benzoic anhydride. 

The anodic oxidation of the carboxylate anion 1 of a carboxylate salt to yield an alkane 3 is known as the Kolbe electrolytic synthesis By decarboxylation alkyl radicals 2 are formed, which subsequently can dimerize to an alkane. The initial step is the transfer of an electron from the carboxylate anion 1 to the anode. The carboxyl radical species 4 thus formed decomposes by loss of carbon dioxide. The resulting alkyl radical 2 dimerizes to give the alkane 3 " ... 

Suitable starting materials for the Kolbe electrolytic synthesis are aliphatic carboxylic acids that are not branched in a-position. With aryl carboxylic acids the reaction is not successful. Many functional groups are tolerated. The generation of the desired radical species is favored by a high concentration of the carboxylate salt as well as a high current density. Product distribution is further dependend on the anodic material, platinum is often used, as well as the solvent, the temperature and the pH of the solution." ... 

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