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Aza-Diels–Alder Reaction
The aza-Diels–Alder reaction converts imines and dienes to tetrahydropyridines. This organic reaction is a modification of the Diels–Alder reaction. The nitrogen atom can be part of the diene or the dienophile. The imine is often generated in situ from an amine and formaldehyde. An example is the reaction of cyclopentadiene with benzylamine to an aza norbornene. In the enantioselective Diels–Alder (DA) reaction of an aniline, formaldehyde and a cyclohexenone catalysis, catalyzed by (S)-proline even the diene is masked. The catalytic cycle starts with the reactions of the aromatic amine with formaldehyde to the imine and the reaction of the ketone with proline to the diene. The second step, an endo trig cyclisation, is driven to one of the two possible enantiomers (99% enantiomeric excess, ee) because the imine nitrogen atom forms a hydrogen bond with the carboxylic acid group of proline on the Si face. Hydrolysis of the final complex releases the product and regenerat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otto Diels
Otto Paul Hermann Diels (; 23 January 1876 – 7 March 1954) was a German chemist. His most notable work was done with Kurt Alder on the Diels–Alder reaction, a method for diene synthesis. The pair was awarded the Nobel Prize in Chemistry in 1950 for their work. Their method of synthesizing cyclic organic compounds proved valuable for the manufacture of synthetic rubber and plastic. He completed his education at the University of Berlin, where he later worked. Diels was employed at the University of Kiel when he completed his Nobel Prize–winning work, and remained there until he retired in 1945. Diels was married, with five children. He died in 1954. Early life Diels was born on 23 January 1876 in Hamburg, Germany, and moved with his family to Berlin when he was two years old. He studied in Berlin at Joachimsthalsches Gymnasium before attending the University of Berlin starting in 1895. While at university, Diels studied chemistry under Emil Fischer, eventually g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
