论文信息 - A NEW METHOD FOR CYCLOPENTENONE ANNELATION VIA THE REARRANGEMENT OF BICYCLIC CYCLOPROPYL KETONES. SYNTHESES OF BICYCLO[4.3.0] NON-6-EN-8-ONE AND BICYCLO[5.3.0]DEC-7-EN-9-ONE

A NEW METHOD FOR CYCLOPENTENONE ANNELATION VIA THE REARRANGEMENT OF BICYCLIC CYCLOPROPYL KETONES. SYNTHESES OF BICYCLO[4.3.0] NON-6-EN-8-ONE AND BICYCLO[5.3.0]DEC-7-EN-9-ONE

A new sequence for cyclopentenone annelation is described which involves the rearrangement of protonated bicyclic acetylcyclopropanes as a key step. Applications of the annelation procedure to cyclohexene and cycloheptene afforded the bicyclo[4.3.0]nonane and bicyclo[5.3.0]decane frameworks, respectively. Further elaboration of the bicyclodecane derivative provides a simple and efficient synthetic route to 2-substituted azulenes.

T. Nakai | M. Okawara | E. Wada

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