Carbonic acid anhydrides carbonates

SYNS ANHYDRIDE CARBONIQUE (FRENCH) CARBON DIOXIDE, refrigerated Uquid (UN 2187) (DOT) CARBON DIOXIDE, soKd (UN 1845) (DOT) CARBONIC ACID ANHYDRIDE CARBONIC ACID GAS CARBONIC ANHYDRIDE CARBON OXIDE DRY ICE DRY ICE (UN 1845) (DOT) KHLADON 744 KOHLENDIOXYD (GERMAN) KOHLENSAEURE (GERMAN) R 744... 

SYNONYMS carbonic acid anhydride, carbonic acid gas, carbonic anhydride, carbon oxide, dry ice. 

Synonyms Carbonic acid anhydride Carbonic acid gas Carbonic anhydride Dry ice... 

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). 

Chemical Properties The formation of salts with acids is the most characteristic reaction of amines. Since the amines are soluble in organic solvents and the salts are usually not soluble, acidic products can be conveniendy separated by the reaction with an amine, the unshared electron pair on the amine nitrogen acting as proton acceptor. Amines are good nucleophiles reactions of amines at the nitrogen atom have as a first step the formation of a bond with the unshared electron pair of nitrogen, eg, reactions with acid anhydrides, haUdes, and esters, with carbon dioxide or carbon disulfide, and with isocyanic or isothiocyanic acid derivatives. 

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. 

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). 

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). 

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. 

A) A mixture of 333 parts of 4-(1 -piperazinyDphenol dihydrobromide, 11.2 parts of acetic acid anhydride, 42 parts of potassium carbonate and 300 parts of 1,4-dioxane is stirred and refluxed for 3 days. The reaction mixture is filtered and the filtrate is evaporated. The solid residue is stirred in water and sodium hydrogen carbonate is added. The whole is stirred for 30 minutes. The precipitated product is filtered off and dissolved in a diluted hydrochloric acid solution. The solution is extracted with trichloromethane. The acid aqueous phase is separated and neutralized with ammonium hydroxide. The product is filtered off and crystallized from ethanol, yielding 5.7 parts of 1 acetyl-4-(4-hydroxyphenyl)piperazine MP 181.3°C. 

The phenyl ether oxygen atoms allow the two borazaphenanthrene rings to pivot with respect to each other, therefore this dimeric boronic acid anhydride can potentially exist in two isomeric forms, either face-to-face or helical (Fig. 18). In the face-to-face form the boron atoms of the bis(borazaphe-nanthrene) moieties have syn-orientation, while they have approximate anti-orientation in the helical form. Compound 68 has been characterized by X-ray crystallography in the helical form [109]. The dimensions of the cavity can be described by the transannular C C contacts between the carbon atoms in 2-position of the phenyl ether units, which have values of 5.12 and 6.21 A. 

C15H21NO5) see Gusperimus trihydrochloride 4-[hydroxy[5-[[(phenylmethoxy)carhonyl]amino]pen-tyl]amino]-4-oxobutanoic acid (C,7H24N20ft 106410-46-2) see Deferoxamine D-a-(4-hydroxyphenyl)-tx-(2-methoxycarbonyl-l-methyl-cthenylamino)acetic acid anhydride with monoethyl carbonate... 

C 7H,203 5675-70-7) see Bisantrene (R)-(-i)-tetrahydrofuran-2-carboxylic acid (CjHgOj 87392-05-0) see Faropenem sodium ( )-tetrahydrofuran-2-carboxylic acid (CjHgOg 16874-33-2) see Alfuzosin Faropenem sodium tetrahydro-2-furancarboxylic acid anhydride with ethyl hydrogen carbonate (CgHijO, 167391-50-6) see Alfuzosin... 

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 presence of impurities can cause a shift in the dissociation point. It implies that the equilibrium temperature and pressure of the carbonate decomposition reaction are shifted. The effect of silica is particularly illustrative in the case of limestone. If silica is present as an impurity, it lowers the decomposition point of limestone. The acid anhydride silica slags combines with the basic calcium oxide according to following ... 

Alternative paths for decomposition of the metal carboxylate can lead to ketones, acid anhydrides, esters, acid fluorides (1,11,22,68,77,78), and various coupling products (21,77,78), and aspects of these reactions have been reviewed (1,11). Competition from these routes is often substantial when thermal decomposition is carried out in the absence of a solvent (Section III,D), and their formation is attributable to homolytic pathways (11,21,77,78). Other alternative paths are reductive elimination rather than metal-carbon bond formation [Eq. (36)] (Section III,B) and formation of metal-oxygen rather than metal-carbon bonded compounds [e.g., Eqs. (107) (119) and (108) (120). Reactions (36) and (108) are reversible, and C02 activation (116) is involved in the reverse reactions (48,120). 

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... 

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