Ethyl acetate ethylidene diacetate

Carbonylation acetic acid, acetic anhydride, methyl acetate, methyl formate Reductive carbonylation acetaldehyde, ethanol, ethyl acetate, ethylidene diacetate Oxidative carbonylation dimethyl carbonate, dimethyl oxalate... 

Water also causes a change in the reaction medium, which may be advantageous. A drawback of the reducing medium in the Eastman process is that in addition to acetic anhydride, the by-product ethylidene diacetate is formed, CH3CH(AcO)2. This can be thermally decomposed to vinyl acetate and acetic acid, or it can be reduced to ethyl acetate, which in the recycle would lead eventually to propionic acid. 

In the 1940 s, in addition to these operations, two other processes became important. Acetic acid was made by reacting methanol with carbon monoxide, and acetic anhydride was being made by the ethylidene diacetate process, which in effect is the dehydration of acetic acid to the anhydride by the use of acetylene. Fermentation ethyl alcohol was converted to acetic acid via acetaldehyde as well as by the direct oxidation of ethyl alcohol. A new operation on the Gulf Coast was also based on acetaldehyde. However, the acetaldehyde is made by the direct oxidation of liquefied petroleum gas. A further process for the production of these materials, in which acetaldehyde is oxidized in one step to a mixture of anhydride and acid, was also begun. 

Ethylidene Diacetate, Ethyl Acetate, Propionic Acid, and Vinyl Acetate via Hydrocarbonylation of Methyl Acetate... 

An extension of the technology associated with carbonylation of methyl acetate, namely the use of synthesis gas rather than CO alone, enables the production of other members of the acetyl chemicals family, in particular ethyl acetate, and the important monomer, vinyl acetate, via a pivotal intermediate ethylidene diacetate (1,1-diacetoxyethane). 

Because of its ready reactivity, ethylidene diacetate is normally formed from methyl acetate and used in situ, to give, for example, ethyl acetate and propionic acid, although a heterogeneous bifunctional catalyst immobililized on an insoluble polymer support has been described for the specific production of ethylidene diacetate from both dimethyl ether and methyl acetate (35). 

The conversions of acetic anhydride to acetaldehyde and of ethylidene diacetate to ethyl acetate both involve hydrogenolysis of C—O bonds, whereas the hydrogenation of acetaldehyde to ethanol involves 0=0 reduction. An appropriate choice of hydrogenolysis versus hydrogenation catalyst functions should enable discrimination between the reaction pathways and the development of highly selective processes to both ethyl acetate and propionic acid, respectively. However, a clear disadvantage common to both is the requirement for recycling of stoichiometric quantities of acetic acid (see the next section). 

Isovaleric Acid (coniintbed) Ethylidene diacetate Ethyl oxalate Glycol diacetate Allyl sulfide 2-Ethoxyethyl acetate... 

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