We describe a triflic acid promoted cascade reaction of adamantane derivatives consisting of a decarboxylation of N-methyl protected cyclic carbamates and a subsequent intramolecular nucleophilic 1,2-alkyl shift to generate ring contracted iminium triflates. This reaction expands the family of similar transformations, such as Wagner-Meerwein-, Demjanov-Tiffeneau-, Meinwald- or (semi-)pinacol-rearrangement. It allows the preparation of noradamantane derivatives in a few steps, starting from simple hydroxy-substituted adamantane precursors.

Department of Organic Chemistry Faculty of Science Charles University Prague Hlavova 8 128 40 Praha Czech Republic

Institute of Inorganic and Analytical Chemistry Justus Liebig University Heinrich Buff Ring 17 35392 Giessen Germany

Institute of Organic Chemistry Justus Liebig University Heinrich Buff Ring 17 35392 Giessen Germany

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Synthesis of 1,2-Disubstituted Adamantane Derivatives by Construction of the Adamantane Framework

Annulated carbamates are precursors for the ring contraction of the adamantane framework