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Succinic acid (/ s ə k ˈ s ɪ n ɪ k /) is a dicarboxylic acid with the chemical formula (CH 2) 2 (CO 2 H) 2. [5] In living organisms, succinic acid takes the form of an anion, succinate, which has multiple biological roles as a metabolic intermediate being converted into fumarate by the enzyme succinate dehydrogenase in complex 2 of the electron transport chain which is involved in making ...
Chemical structure of an alkylsuccinic anhydride derived from octadecene. Maleic anhydride undergoes the Alder-ene reaction with alkenes to give alkenylsuccinic anhydrides. Such compounds are sizing agents in the paper industry. In this role, the anhydride is proposed to form an ester with the hydroxyl groups on the cellulose fibers. [8]
For both these scenarios the mass based succinic acid yield is 1.12 g/g. This implies that the theoretical maximum yield is such that more succinic acid is formed than glucose consumed due to the fixation of carbon dioxide. Figure 3: Metabolic pathway for producing succinic acid without byproducts. NADH balance is achieved by oxidative TCA branch.
So succinic acid will yield succinic anhydride. For acids with carboxylic groups at position 1 and 6 this dehydration causes loss of carbon dioxide and water to form a cyclic ketone, for example, adipic acid will form cyclopentanone. [26]
The mixture of end products produced by mixed acid fermentation includes lactate, acetate, succinate, formate, ethanol and the gases H 2 and CO 2. The formation of these end products depends on the presence of certain key enzymes in the bacterium. The proportion in which they are formed varies between different bacterial species. [4]
All of the processes of Shiina macrolactonization consist of reversible reactions, with the exception of the last cyclization step.At the first stage of the reaction, mixed anhydride (MA) is produced quickly under mild conditions; at the second stage, a faster cyclization of the MA prevents an increase in MA concentration.
The Stobbe condensation entails the reaction of an aldehyde or ketone with an ester of succinic acid to generate alkylidene succinic acid or related derivatives. [1] The reaction consumes one equivalent of metal alkoxide. Commonly, diethylsuccinate is a component of the reaction. The usual product is salt of the half-ester.
Therefore, the aromatic carboxylic acid anhydride and the mixed anhydride (MA) coexist in the system. Furthermore, aliphatic carboxylic acid anhydride produced via disproportionation of the MA is simultaneously present in the system; thus, it is directly used as a mixture without being separated.