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Please login to access the full content or check if you have access via Variation 1: Polycyclic Ketones by Intramolecular [2+2] Cycloaddition of ­Monoalkylketenes with Alkenyl Groups

DOI: 10.1055/sos-SD-023-00535

Tidwell, T. T.Science of Synthesis, (200623606.

The intramolecular cyclization of ketenes with C=C bonds is a powerful technique for the construction of polycyclic rings, and is the subject of several reviews.[‌142‌‌144‌] In the absence of other reagents to react with the ketene by intermolecular reactions, cyclization processes are favored, and some very strained rings can be obtained by this process. The conformational constraints on the reaction usually result in a high degree of stereoselectivity. Monoalkylketenes are not highly reactive, and so these cyclizations are most successful with highly nucleophilic alkenyl groups or when the reactive groups are held close together in cyclic structures.

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