Carbonic acid anhydrides chloride

Appropriate quenching of a reductively formed lithium enolate with a carboxylic acid anhydride, chloride, methyl chloroformate or diethyl phosphorochloridate yields the corresponding enol esters, enol carbonates or enol phosphates. These derivatives may be transformed into specific alkenes via reductive cleavage of the vinyl oxygen function, as illustrated by the example in Scheme 8. 

Where acid chlorides are difficult to obtain, Weinstock s method of using mixed carboxylic-carbonic acid anhydrides can be helpful. The acid to be converted into its azide is treated with ethyl chlorofor-mate and base, the ethyl carbonate moiety is then displaced by azide ion. The method has been used in the penicillin field . It is not general, however when the alkanoyl part of the mixed anhydride is sterically hindered, the azide ion displaces it instead of the carbonate moiety, and ethyl azidoformate is produced Cyclic anhydrides can be opened by azide ion, to give the salts of omega-azidocarbonyl acids, such as Na+ "OOCCHaCHaCONa . 

Nucleophilic acyl substitution (Sections 20 4 20 6 and 20 12) Acylation of am monia and amines by an acyl chloride acid anhydride or ester is an excep tionally effective method for the for mation of carbon-nitrogen bonds... 

Carbon dioxide can be considered the acid anhydride of carbonic acid. Accordingly, it reacts with ben2ene, albeit ia low yield, to give ben2oic acid and ben2ophenone ia the presence of aluminum chloride. 

Ahyl alcohol undergoes reactions typical of saturated, aUphatic alcohols. Ahyl compounds derived from ahyl alcohol and used industriahy, are widely manufactured by these reactions. For example, reactions of ahyl alcohol with acid anhydrides, esters, and acid chlorides yield ahyl esters, such as diahyl phthalates and ahyl methacrylate reaction with chloroformate yields carbonates, such as diethylene glycol bis(ahyl carbonate) addition of ahyl alcohol to epoxy groups yields products used to produce ahyl glycidyl ether (33,34). 

Cellulose esters are commonly derived from natural cellulose by reaction with organic acids, anhydrides, or acid chlorides. Cellulose esters of almost any organic acid can be prepared, but because of practical limitations esters of acids containing more than four carbon atoms have not achieved commercial significance. 

Note Maximum ambient levels for ethylene oxide are 0.3 ppb at the plant fence. Maximum total emissions of the VOCs acetaldehyde, acrylic acid, benzyl chloride, carbon tetrachloride, chlorofluorocarbons, ethyl acrylate, halons, maleic anhydride, 1,1,1-trichlorethane, trichloroethylene, and trichlorotoluene are 20 mg/Nnf. Maximum total heavy metal emissions are 1.5 mg/Nnf. 

Dicarboxylic acid dichlorides with less than seven carbon atoms do not react to give tetraketones similar to 117, but instead undergo an intramolecular acylation (72) to give on hydrolysis the vinylogous acid anhydride (118), e.g., from succinyl chloride and the enamine (113). 

Kohlensaure,/. carbonic acid carbon dioxide, -anhydrid, rt. carbonic anhydride (carbon dioxide), -ausscheidung,/. (Physiol.) c Tbon dioxide excretion, -bestimmer, m. apparatus for determining carbon dioxide, -brot, n, aerated bread, -chlorid, n. carbonyl chloride, -entwickelung,/. evolution of carbon dioxide, -ester, m. carbonic ester, -flasche, /. carbon dioxide cylinder, -gas, n, carbonic add gas (carbon dioxide), -gehalt, m. carbon dioxide content. 

To a solution of 13 parts of compound A and 12 parts by volume of absolute pyridine in 80 parts by volume of absolute dioxane there are added dropwise and under constant stirring 35 parts of 3,4.5-trimethoxybenzoyl chloride dissolved in 70 parts by volume of absolute dioxane in the course of 30 minutes. The mixture is stirred for a further 3 hours at a temperature of 100°C and the excess solvent is then evaporated in vacuo. The residue of the evaporation is treated with ethyl acetate and saturated sodium carbonate solution, whereafter the organic phase is separated, treated with water, dried with sodium sulfate and the solvent is removed in vacuo. The residue thus obtained is taken up In ether and separated from 4 parts of insoluble trimethoxybenzoic acid anhydride by filtration. After evaporation of the ether there are obtained 32.5 parts of N,N -dimethyl-N,N -bis-[3-(3,4,5-trlmethoxybenzoxy)-propyl] -athylene diamine, corresponding to a yield of 86% of the theoretical. MP 75°C to 77°C. 

Geranyl chloride can be prepared from geraniol by the careful use of triphenylphosphine in carbon tetrachloride. Tris(dimethylamino)phosphine reacts with carbon tetrachloride to form the complex (42) which can be used to form the enol esters (43) from acid anhydrides. Similarly, aldehydes form the alkenes (44), and esters or amides of trichloroacetic acid are converted to glycidic esters. ... 

The CO-X bond breaking is the result of an electrophilic attack (on the carbonyl oxygen atom, hence the catalytic role of acids in these rupture reactions) or a nucleophilic one (on the carbonyl carbon atom whose positive property is due to the X electron-withdrawing property). The dangers of this type of reaction come from its speed and high exothermicity and/or instability of the products obtained in some cases. The accidents that are described below can make one believe that acid anhydrides in general and acetic anhydride in particular represent greater risks than acid chlorides since they constitute the accident factor of almost all accidents described. This is obviously related to their frequent use in synthesis rather than acid chlorides, that are rarely used. 

Derivatives are prepared from the appropriate acid anhydride, or occasionally the acid chloride, usually in the presence of a base such as pyridine, triethylamine, or N,N-dimethyl-4-amlnopyridine at elevated temperatures [474-482]. Acylation of amines and phenols (not alcohols) in aqueous solution in the presence of potassium carbonate has been demonstrated (448,483,484), but does not constitute m l practice as reactions are generally performed under i Arous conditions. 

Acylation of carbon nucleophiles can also be carried out with more reactive acylating agents such as acid anhydrides and acyl chlorides. These reactions must... 

The third procedure illustrated by this preparation involves the reaotion of ketones with trifluoromethanesulfonic anhydride in a solvent such as pentane, methylene chloride, or carbon tetrachloride and in the presence of a base such as pyridine, lutidine, or anhydrous sodium carbonate.7-11,15 This procedure, which presumably involves either acid-catalyzed or base-catalyzed enolization of the ketone followed by acylation of the enol with the acid anhydride, has also been used to prepare other vinyl sulfonate esters such as tosylates12 or methanesulfonates.13... 

Acyl chlorides are converted in good yield into symmetrical carboxylic acid anhydrides upon treatment with dilute aqueous sodium hydroxide at -I0°C in the presence of a tetra- -butylammonium salt [76, 77]. Yields are considerably lower when Aliquat is used. In a similar manner, chloroformates and ethyl oxalyl chloride are converted into carbonic hemi-ester anhydrides. 

The acylation of formamidoxime should lead to oxadiazoles unsubstituted in the 3-position. While benzoylation with benzoyl chloride is reported to give dibenzhydroxamic acid 45), 0-acylated formamidoxime could be prepared in good yields with acetic anhydride, the mixed anhydride of acetic and ethyl carbonic acid, benzoic anhydride and benzoyl azide. The cyclization of these esters of formamidoxime into 5-substituted oxadiazoles has been accomplished by heating in an aqueous medium. 

Benzoic anhydride has been prepared in rather a poor yield by the action of benzoyl chloride on sodium benzoate,2 barium oxide at 1500,3 benzoic acid at 160-200°,4 sodium nitrite,5 lead nitrate,6 or anhydrous oxalic acid 7 also by treating sodium benzoate with phosphorus pentachloride8 or sulfur chloride.9 More important methods consist in treating benzotrichloride with sulfuric acid,10 and in the action of sodium carbonate upon benzoyl chloride in presence of pyridine.11... 

Aluminum foil, Iodine powder. Carbon disulfide, 1,4,6,9-Tetrabromodiamantane, Sodium bisulfite. Hydrochloric acid. Methanol, Acetonitrile, Acetone, Sodium hydroxide. Magnesium sulfate. Potassium permanganate. Toluene Methylene chloride, 2-Bromomethanol, Trioxane, Aluminum chloride. Magnesium sulfate, Nitroform, Acetone, Sodium bicarbonate. Hexane, Silver nitrate. Acetonitrile 1,2-Dichloroethane, HexamethyldisUane, Iodine, Cyclohexane, 1,3-Dioxolane, Nitroform, Methylene chloride, Dimethylformamide, Sodium sulfate. Hydrochloric acid. Magnesium sulfate. Nitric acid. Sulfuric acid Sulfuryl chloride. Acetic anhydride. Nitric acid. Sodium bicarbonate. Sodium sulfate Nitric acid. Sulfuric acid, Malonamide Nitric acid. Sulfuric acid, Cyanoacetic acid Sulfuric acid, Acetasalicyclic acid. Potassium nitrate Nitroform, Diethyl ether, 1-Bromo-l-nitroethane, Sodium sulfuate... 

Nitric acid. Kerosene, Ammonium picramate. Ethanol Sodium picramate. Hydrochloric acid. Sodium nitrate Nitric acid. Diethanolamine, Acetic anhydride. Acetyl chloride. Acetone, Potassium carbonate Acetic anhydride. Hydrochloric acid. Diethanolamine, Methylene chloride. Nitric acid. Sodium bicarbonate Nitric acid. Diethanolamine, Hydrogen chloride. Sodium bicarbonate Diisopropylamine, Nitric acid... 

Nitric acid, N-Methyl gluconamide. Acetic anhydride. Sodium bicarbonate. Methanol Dimethylurea, Nitric acid, Sulfuric acid. Methylene chloride, Sodium carbonate Anhydrous hydrazine, Cyanogen bromide, Isopropyl alcohol, Sodium nitrite, Sodium bicarbonate, Copper nitrate trihydrate, Nitric acid, Diethyl ether, Dimethyl sulfate... 

Benzene, Arsenic trichloride, Aluminum chloride. Hexanes Acetic anhydride. Nitric acid, Hexamine, Acetic acid, Methylene chloride. Sodium bicarbonate, Magnesium sulfate, Dioxane, Hydrogen chloride, Acetone, Sodium azide m-phenylenediamine, Methanol, Sodium carbonate, Ethyl chloromate, Ethylene glycol dimethyl ether, Sulfuric acid, Nitric acid... 

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