Abstract
Two pathways are presented, which allow for the selective cleavage
of the C1/C8b bond in the title compounds. The first reaction
was found by serendipity when reductive debenzylation was attempted
on a heteroanellated azabicyclo[4.2.0]octane.
It yielded an eight-membered lactam ring (azocane). The second transformation
relies on a rationally designed 1,2-rearrangement reaction, which
was introduced because attempts to induce classical Wagner-Meerwein-type
1,2-shifts did not meet with success. The reaction, a retro-benzilic
acid rearrangement, allowed for the conversion of a heteroanellated
hydroxycyclobutanecarboxylate into the respective cyclopentadione
(76% yield).
Key words
metal reductions - lactams - photochemistry - cyclobutanes - rearrangements - fragmentations
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