Cu-catalyzed borylative cyclization of allene cyclohexanediones has been described through a tandem β-borylation and intramolecular allylic addition process, affording borylated cis-decalinols with excellent yields and diastereoselectivities. A good enantioselectivity is also achieved in the asymmetric version. The hemiboronate group in the cyclization products could be subjected to several useful transformations.
