No abstract

Allylic oxidation of hydrocarbon substrates is the foundation of many industrial and fine-chemical production processes. Direct allylic oxidation of cycloalkenes (C5 - 8) has been widely discussed in the chemical literature. However, certain mechanistic details related to the presence of allylic free radicals have yet to be fully resolved. The corresponding copper-catalyzed allylic amination reaction has not been previously achieved. We report the first examples of this class of amination reaction using saccharin and bis-p-toluenesulfonamide as nitrogen sources and t-BuOOH and PhI(saccharinate)2 as oxidants. Kinetic studies on stoichiometric model reactions demonstrate that the oxidant is not involved in the RDS of the transformation, and studies with 3,3,6,6-tetradeuteriocyclohexene conclusively show a mechanistic dichotomy between the catalytic oxidation and amination reactions. Both oxidative processes involve η1-allyl intermediates, and regiochemical results are a consequence of discrete copper complexes. A mechanistic rationale involving allylic transpositions explains this mechanism dichotomy.

Die Deprotonisierung von Diisopropylformamid mit tert.‐Butyllithium bei ‐95°C in einem 4:4: 1‐Gemisch von Tetrahydrofuran, Diäthyläther und Pentan ergibt in hoher Ausbeute das Lithiumamid (II), das mit Benzophenon unter Addition das Hydroxyamid (III) bildet und den Ester (IV) zum Ketoamid (V) substituiert.

Die 1 ,3‐Benzo‐dithiole (I) werden mit Butyllithium in die Anionen (II) übergeführt, aus denen mit elektrophilen Reagentien die ,Addukte (III) erhalten werden.