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The Wagner-Jauregg reaction is a classic organic reaction in organic chemistry, named after Theodor Wagner-Jauregg [] (son of Julius Wagner-Jauregg), describing the double Diels–Alder reaction of 2 equivalents of maleic anhydride with a 1,1-diarylethylene.
Its susceptibility to 1,4-addition reactions is illustrated by its hydrocyanation. Like many dienes, it undergoes Pd-catalyzed reactions that proceed via allyl complexes. [28] It is a partner in Diels–Alder reactions, e.g. with maleic anhydride to give tetrahydrophthalic anhydride. [29]
Polybutadiene [butadiene rubber, BR] is a synthetic rubber. It offers high elasticity, high resistance to wear, good strength even without fillers, and excellent abrasion resistance when filled and vulcanized. "Polybutadiene" is a collective name for homopolymers formed from the polymerization of the monomer 1,3-butadiene.
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 terms of the stereoselectivity of the reaction between maleic anhydride and cyclopentadiene, the endo-product is favored, a result best explained through FMO theory. The maleic anhydride is an electron-withdrawing species that makes the dieneophile electron deficient, forcing the regular Diels–Alder reaction.
The Diels–Alder reaction was one step in an early preparation of the steroids cortisone and cholesterol. [75] The reaction involved the addition of butadiene to a quinone. Diels-Alder in the total synthesis of cortisone by R. B. Woodward. Diels–Alder reactions were used in the original synthesis of prostaglandins F2α and E2. [76]
The reaction is named for Anthony B. Baylis and Melville E. D. Hillman, two of the chemists who developed the reaction at Celanese; and K. Morita, who published earlier work [3] on the same. The MBH reaction offers several advantages in organic synthesis: It combines easily prepared starting materials with high atom economy.
For example, an analog for the Diels-Alder reaction is the quadricyclane-DMAD reaction: In the (i+j+...) cycloaddition notation i and j refer to the number of atoms involved in the cycloaddition. In this notation, a Diels-Alder reaction is a (4+2)cycloaddition and a 1,3-dipolar addition such as the first step in ozonolysis is a (3+2)cycloaddition.