Organic acid halides

Organic halides, organic acid halides, esters and salts... 

Silica surfaces are the chief source of activity in columns for SFC and, even though many of the columns are well deactivated, the residual silanol sites can lead to tailing or adsorption of analytes. The low surface area of capillary columns is responsible for much higher levels of inertness than their packed counterparts based on silica particles. Capillary columns have been used successfully in the analysis of active compounds, including isocyanates, acid halides, organic acids, amines, peroxides, azo compounds, and many others. The low temperatures required for elution make analysis of active and labile compounds viable. 

In the former, it gives precipitates with halides (except the fluoride), cyanides, thiocyanates, chromates(VI), phosphate(V), and most ions of organic acids. The silver salts of organic acids are obtained as white precipitates on adding silver nitrate to a neutral solution of the acid. These silver salts on ignition leave silver. When this reaction is carried out quantitatively, it provides a means of determining the basicity of the acid... 

Polonium is readily dissolved in dilute acids, but is only slightly soluble in alkali. Polonium slats of organic acids char rapidly halide amines are reduced to the metal. 

Nitric acid, fuming Organic matter, nonmetals, most metals, ammonia, chlorosulfonic acid, chromium trioxide, cyanides, dichromates, hydrazines, hydrides, HCN, HI, hydrogen sulflde, sulfur dioxide, sulfur halides, sulfuric acid, flammable liquids and gases... 

Vinyllithium [917-57-7] can be formed direcdy from vinyl chloride by means of a lithium [7439-93-2] dispersion containing 2 wt % sodium [7440-23-5] at 0—10°C. This compound is a reactive intermediate for the formation of vinyl alcohols from aldehydes, vinyl ketones from organic acids, vinyl sulfides from disulfides, and monosubstituted alkenes from organic halides. It can also be converted to vinylcopper [37616-22-1] or divinylcopper lithium [22903-99-7], which can then be used to introduce a vinyl group stereoselectively into a variety of a, P-unsaturated systems (26), or simply add a vinyl group to other a, P-unsaturated compounds to give y, 5-unsaturated compounds. Vinyllithium reagents can also be converted to secondary alcohols with trialkylb o r ane s. 

Esterification. Esters are formed by the reaction of ethanol with inorganic and organic acids, acid anhydrides, and acid halides. If the inorganic acid is oxygenated, eg, sulfuric acid, nitric acid, the ester has a carbon—oxygen linkage that is easily hydrolyzed (24—26). 

Organic acids yield lemon-yellow zones on a blue background [1]. Halide ions migrate as ammonium salts in ammoniacal mobile phases and are also colored yellow. The colors fade rapidly in the air. This can be delayed for some days by covering the chromatogram with a glass plate. 

Experimental data show that at the usual concentrations (10 to lOM), most salts and also the hydroxides of alkali metals are strong electrolytes. This is true also for some inorganic acids HCl, HCIO4, and others. Weak electrolytes are the organic acids and the hydroxides of metals other than alkah. Few electrolytes of the intermediate type (with moderate values of a) exist in particular, certain transition-metal halides such as ZnClj, Znl2, and CdCl2 are in this category. 

When there is no diluent, organic acid chlorides and metal halides react very violently with DMSO. This goes for acetyl chloride, benzenesulphonyl (C6H5SO2CI), cyanuryl chloride, phosphorus and phosphoryl trichlorides, tetrachlorosilane, sulphur, thionyl, and sulphuryl chlorides. With oxalyl chloride, the reaction is explosive at ambient temperature, but can be controlled at -60°C in a solution with dichloromethane. The dangerous reactions are thought to be... 

The ion-exchange process is applicable for removing a broad range of ionic species from water containing all metallic elements, inorganic anion such as halides, sulfates, nitrates, cyanides, organic acids such as carboxylics, sulfonics, some phenols at sufficiently alkaline pH conditions, and organic amines at sufficiently acidic conditions. 

Hydride-promoted reactions are also well known, such as the acrylic and vinylacrylic syntheses (examples 7-10, Table VII). Some less-known compounds, which form in the presence of halide ions added to tetracar-bonylnickel, have been described by Foa and Cassar (example 11, Table VII). Reaction of allene to form methacrylates, and of propargyl chloride to give itaconic acid (via butadienoic acid), have been reported (examples 13 and 14, Table VII). 1,5-Hexadiene has been shown to be a very good substrate to obtain cyclic ketones in the presence of hydrogen chloride and tetracarbonylnickel (example 15, Table VII). The latter has also been used to form esters from olefins (example 16, Table VII). In the presence of an organic acid branched esters form regioselectivity (193). 

Acyl-transfer reactions are some of the most important conversions in organic chemistry and biochemistry. Recent work has shown that adjacent cationic groups can also activate amides in acyl-transfer reactions. Friedel-Crafts acylations are known to proceed well with carboxylic acids, acid chlorides (and other halides), and acid anhydrides, but there are virtually no examples of acylations with simple amides.19 During studies related to unsaturated amides, we observed a cyclization reaction that is essentially an intramolecular acyl-transfer reaction involving an amide (eq 15). The indanone product is formed by a cyclization involving the dicationic species (40). To examine this further, the related amides 41 and 42 were studied in superacid promoted conversions (eqs 16-17). It was found that amide 42 leads to the indanone product while 41... 

We use the term conventional acid to designate stable acids such as the hydrogen halides and the common mineral and organic acids, in order to distinguish them from the complex acids such as the hydrates of metal halides and the adducts formed from, for example, trichloroacetic acid and titanium tetrachloride. 

Subsequently it was found that in solvents of low dielectric constant (hydrocarbons and carbon tetrachloride) neither polymerisations [2] nor alkylations [3] and isomerisations [4] could be effected by a metal halide alone, but that a third substance, called the co-catalyst, is required. The most common, and indeed ubiquitous co-catalyst is water other substances proved to act in this capacity are alcohols [5], organic acids [6] and nitro-compounds [7]. In each case the catalysis can be ascribed to a complex protonic acid PXnA H+ ... 

Organic acid halides/anhydrides Acetic anhydride, acetyl chloride... 

Classical organic chemistry provides a wide variety of potential analytes for electron ionization, the only limitation being that the analyte should be accessible to evaporation or sublimation without significant thermal decomposition. These requirements are usually met by saturated and unsaturated aliphatic and aromatic hydrocarbons and their derivatives such as halides, ethers, acids, esters, amines, amides etc. Heterocycles generally yield useful El spectra, and flavones, steroids, terpenes and comparable compounds can successfully be analyzed by El, too. Therefore, El represents the standard method for such kind of samples. 

Guanamines are obtainable from biguanides by the action of reagents other than esters. These include the amides, halides and anhydrides of organic acids, as well as the acids themselves. 

Research involving condensation organometallic polymers was catalyzed by the observation that many organometallic halides possess a high degree of covalent character within their composite structure and that they can behave as organic acid chlorides in many reactions, such as hydrolysis... 

The mechanisms of the other methods of Intensification are more in doubt (cf. review by Sheppard el ah, 76). These methods include bathing the photographic material in a solution of silver salt, in a solution of hydrogen peroxide or sodium perborate (Vanselow et ah, 77), in a solution of aurous thiocyanate (James et ah, 31) or by fuming the material in the vapor of certain organic acids (Mueller and Bates, 78) or of ammonia. Such treatment may result in an increase in the effective size of the sub-nuclei, or simply in bringing about more favorable conditions for development at the silver/silver halide interface. 

Aluminium forms numerous series of complex derivatives, the halogen salts showing a marked tendency to form molecular compounds with other metallic halides, with acid chlorides, with chlorides of organic acids, and with ammonia. 

The conversion of carboxylic acids into corresponding acid halides (COF or COC1) involves an increase of the reactivity of organic acids and can authorize subsequent reactions not easy to perform in soft conditions with the parent acid. For example, amides and esters can be quantatively obtained by treatment of acid halide derivatives by ammonia and methanol vapor respectively ... 

Volume 10 is devoted to formation and solvolysis of esters and related reactions, with discussion of the effect of neighbouring groups and biological implications, e.g. enzyme action, where appropriate. The first chapter deals mainly with esters of the inorganic acids of phosphorus and sulphur, Chapter 2 with the formation and solvolysis of esters of organic acids and the final chapter with the solvolysis of related derivatives of carboxylic acids, e.g. halides, amides, anhydrides, cyanides, carbamic acid derivatives. 

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