Acetic acid anhydride syntheses

Torrence P (2002) Carbonylations synthesis of acetic acid and acetic acid anhydride from methanol. In Cornils B, Herrmann WA (eds) Applied homogeneous catalysis with organometallic compounds, vol 1, 2nd edn. Wiley, Weinheim, p 104... 

Even higher viscosities are typical for polyimides based on tetranuclear diamines, e.g., 4,4 -di-(p-aminophenoxy)-benzophenone and l,l-dichloro-2,2 di(/ -aminophenoxy)-ethylene. Polyimides were prepared according to the method for the synthesis of PCA by low-temperature polycondensation in NMP. Polyimides were prepared by catalytic cyclodehydration of PCA directly in the reaction solutions using the catalytic system pyridine-acetic acid anhydride (1 1) [22] (Scheme 3.5). 

Malonic acid itself can react with aldehydes in the presence of piperidine by way of a Knoevenagel condensation. A decarboxylation occurs after the condensation, and this decarboxylation cannot be avoided. Figure 13.55 shows how the overall reaction can be employed for the synthesis of cinnamic or sorbic acid. This reaction sequence occurs under much milder conditions than the Perkin synthesis of cinnamic acids. (The Perkin synthesis consists of the condensation of aromatic aldehydes with acetic acid anhydride in the presence of sodium acetate.)... 

Synthesis of Acetic Acid and Acetic Acid Anhydride from Methanol 105... 

NHC(O)- moieties This is exemplified by the synthesis of compound (18) from the azide (17), triphenylphosphine and acetic acid anhydride ... 

The synthesis can be realized according to the procedure of Ladenburg (1876) by treatment of 2-aminophenol with acetic acid anhydride. 

Although intensive scientific work has been devoted to strategies for the synthesis of cellulose organic esters, especially with regard to homogeneous reaction conditions and in view of the advent of ionic liquids as reaction media [36], the principles employed for cellulose acetate production have remained the same for decades. Nowadays, only the acetic acid process , that is, the use of acetic acid as the solvent and acetic acid anhydride as reactant, in combination with sulfuric acid as the catalyst, is of industrial relevance [37]. 

PFCAs can also be synthesized by electrochemical fluorination of the corresponding alkanoic acid however, the yield of this reaction is only 10-20%. Slightly higher yields can be obtained by fluorination of the corresponding anhydrides. For example, acetic acid and acetic acid anhydride form perfluoroacetyl fluoride in a 17% and 32% yield, respectively. A major disadvantage of this approach is the formation of water that may form explosive oxygen difluoride. Simple alkanoic acids were, therefore, never useful starting materials for the industrial synthesis of PFCA fluorides. 

Acetic anhydtide [108-24-7] (CH2C0)20, is a mobile, colorless liquid that has an acrid odor and is a more pierciag lacrimator than acetic acid [64-19-7]. It is the largest commercially produced carboxyUc acid anhydride U.S. production capacity is over 900,000 t yearly. Its chief iadustrial appHcation is for acetylation reactions it is also used ia many other appHcations ia organic synthesis, and it has some utility as a solvent ia chemical analysis. 

Acetic Acid and Anhydride. Synthesis of acetic acid by carbonylation of methanol is another important homogeneous catalytic reaction. The Monsanto acetic acid process developed in the late 1960s is the best known variant of the process. 

There are some chemicals that can be made economically from coal or coal-derived substances. Methanol and CO are used to make acetic anhydride and acetic acid. Methanol itself can be made from synthesis gas over a copper-2inc catalyst (see Feedstocks, coal chemicals). 

Synthesis Gas Chemicals. Hydrocarbons are used to generate synthesis gas, a mixture of carbon monoxide and hydrogen, for conversion to other chemicals. The primary chemical made from synthesis gas is methanol, though acetic acid and acetic anhydride are also made by this route. Carbon monoxide (qv) is produced by partial oxidation of hydrocarbons or by the catalytic steam reforming of natural gas. About 96% of synthesis gas is made by steam reforming, followed by the water gas shift reaction to give the desired H2 /CO ratio. 

Production of maleic anhydride by oxidation of / -butane represents one of butane s largest markets. Butane and LPG are also used as feedstocks for ethylene production by thermal cracking. A relatively new use for butane of growing importance is isomerization to isobutane, followed by dehydrogenation to isobutylene for use in MTBE synthesis. Smaller chemical uses include production of acetic acid and by-products. Methyl ethyl ketone (MEK) is the principal by-product, though small amounts of formic, propionic, and butyric acid are also produced. / -Butane is also used as a solvent in Hquid—Hquid extraction of heavy oils in a deasphalting process. 

The synthesis of 2,4-dihydroxyacetophenone [89-84-9] (21) by acylation reactions of resorcinol has been extensively studied. The reaction is performed using acetic anhydride (104), acetyl chloride (105), or acetic acid (106). The esterification of resorcinol by acetic anhydride followed by the isomerization of the diacetate intermediate has also been described in the presence of zinc chloride (107). Alkylation of resorcinol can be carried out using ethers (108), olefins (109), or alcohols (110). The catalysts which are generally used include sulfuric acid, phosphoric and polyphosphoric acids, acidic resins, or aluminum and iron derivatives. 2-Chlororesorcinol [6201-65-1] (22) is obtained by a sulfonation—chloration—desulfonation technique (111). 1,2,4-Trihydroxybenzene [533-73-3] (23) is obtained by hydroxylation of resorcinol using hydrogen peroxide (112) or peracids (113). 

Fig. 2. Synthesis of uma2enil (18). The isonitrosoacetanihde is synthesized from 4-f1iioroani1ine. Cyclization using sulfuric acid is followed by oxidization using peracetic acid to the isatoic anhydride. Reaction of sarcosine in DMF and acetic acid leads to the benzodiazepine-2,5-dione. Deprotonation, phosphorylation, and subsequent reaction with diethyl malonate leads to the diester. After selective hydrolysis and decarboxylation the resulting monoester is nitrosated and catalyticaHy hydrogenated to the aminoester. Introduction of the final carbon atom is accompHshed by reaction of triethyl orthoformate to...

Eastman Chemical Company has operated a coal-to-methanol plant in Kingsport, Tennessee, since 1983. Two Texaco gasifiers (one is a backup) process 34 Mg/h (37 US ton/h) of coal to synthesis gas. The synthesis gas is converted to methanol by use of ICl methanol technology. Methanol is an intermediate for producing methyl acetate and acetic acid. The plant produces about 225 Gg/a (250,000 US ton/a) of acetic anhydride. As part of the DOE Clean Coal Technology Program, Air Products and Cnemicals, Inc., and Eastman Chemic Company are constructing a 9.8-Mg/h (260-US ton/d) slurry-phase reactor for the conversion of synthesis gas to methanol and dimethyl... 

The close relationship of eegonine to tropine is brought out by its Oxidation products, which when chromic anhydride in acetic acid is the agent used are tropinone, CgHijON (p. 74), tropinic acid, CgHi304N (P- 75) and ecgoninic acid, C HnOgN. The latter crystallises from benzene in colourless needles, m.p. 93°, and has been shown by Willstatter and Bode to W-methylpyrrolidone-2-acetic acid, and this was confirmed by Willstatter and Hollander s synthesis of the acid. 

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