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Hünlich base: (re)discovery, synthesis, and structure elucidation after a century
Stephan Rigol1, Lothar Beyer, Lothar Hennig
1Institut für Organische Chemie, Fakultät für Chemie und Mineralogie, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany.
Abstract:
After almost 100 years, the structure of the product of the reaction between 2,4-diaminotoluene and formaldehyde was elucidated: derivative 3, which we call the Hünlich base, was synthesized on a multigram scale and its enantiomers were easily separated in preparative amounts. Furthermore, transformation of the NH2 groups to the corresponding bis-iodides and bis-azides is presented. The latter was also used for desymmetrization by click chemistry.
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