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Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Highly regio- and stereocontrolled formation of functionalized tricyclo[4.2.1.0(2,8)]non-3-enes
Nicolas Toselli1, David Martin, Mathieu Achard
1Université Aix-Marseille, Institut des Sciences Moléculaires de Marseille, ECM, CNRS, UMR 6263, Av. Escadrille Normandie Niemen 13397, Marseille Cedex 20, France.
Abstract:
The electrophilic activations of bicyclo[4.2.1]nonatrienes by 4-isopropyl-1,2,4-triazolinedione, N-iodosuccinimide, or an epoxidation/acidic ring-opening sequence is reported. The subsequent in situ trappings by water, alcohols, or benzoic acids led to original tricyclo[4.2.1.0(2,8)]non-3-enes with high regio- and stereoselectivities. The synthetic potentiality of these synthons is illustrated by the straightforward access to a fused cyclopropane featuring six consecutive controlled stereocenters.
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