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Maleic anhydride is a classic substrate for Diels-Alder reactions. [9] It was used for work in 1928, on the reaction between maleic anhydride and 1,3-butadiene, for which Otto Paul Hermann Diels and Kurt Alder were awarded the Nobel Prize in 1950. It is through this reaction that maleic anhydride is converted to many pesticides and pharmaceuticals.
In industry, maleic acid is derived by hydrolysis of maleic anhydride, the latter being produced by oxidation of benzene or butane. [4] Maleic acid is an industrial raw material for the production of glyoxylic acid by ozonolysis. [8] Maleic acid may be used to form acid addition salts with drugs to make them more stable, such as indacaterol ...
The patent describes the reaction of the alkenes with excess maleic anhydride at 200 °C in an autoclave. The excess alkene is removed by distillation in vacuo, the resulting alkenyl succinic anhydride hydrolyzed with dilute sodium hydroxide solution and the disodium salt reacted with an acid to achieve an alkenebutanedioic acid.
Succinic anhydride hydrolyzes readily to give succinic acid: (CH 2 CO) 2 O + H 2 O → (CH 2 CO 2 H) 2. With alcohols (ROH), a similar reaction occurs, delivering the monoester: (CH 2 CO) 2 O + ROH → RO 2 CCH 2 CH 2 CO 2 H. Succinic anhydride is used in acylations under Friedel-Crafts conditions, as illustrated by the industrial route to the ...
In another process, maleic anhydride is first opened with water or another alcohol to form maleic acid and is then reacted with DCPD where an alcohol from the maleic acid reacts across one of the double bonds of the DCPD. This product is then used to end-cap the UPR resin which yields a product with unsaturation on the end-groups.
The reaction proceeds with about 70% selectivity. About 10% of maleic anhydride is also produced: C 6 H 4 (CH 3) 2 + 7 + 1 / 2 O 2 → C 4 H 2 O 3 + 4 H 2 O + 4 CO 2. Phthalic anhydride and maleic anhydride are recovered by distillation by a series of switch condensers.
Dibutyl maleate can be prepared by the reaction of maleic acid anhydride and 1-butanol in presence of p-toluenesulfonic acid. [3] [4] Uses
Alkyd resins may be classified as drying (including semi drying) and nondrying. Both types are typically produced from dicarboxylic acids or anhydrides, such as phthalic anhydride or maleic anhydride, and polyols, such as trimethylolpropane, glycerine, or pentaerythritol. [5] Alkyds are a synthetic resin and used in items such as paints.