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Enantioselective and Divergent Trienamine-Mediated Reactions of Halogenated Maleimides
Jonas Faghtmann1, Anne Rask Østergaard1, Fabien Fritz1
1Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark.
Abstract:
Halogenated maleimides can undergo either a [4 + 2] cycloaddition or a [4 + 2]/SN2 cascade reaction in an enantioselective and divergent fashion with catalytically formed trienamines. Under mild acidic conditions, [4 + 2] cycloadducts are isolated in good yields with complete diastereoselectivity and high enantioselectivity. With the addition of silver(I) benzoate as a base, a [4 + 2]/SN2 cascade reaction is induced, forming tricyclic norcaranes in moderate to good yields and with excellent overall stereoselectivity. The influence of the halogen effect on the cycloaddition was investigated experimentally, revealing a minimal impact.
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