ja6b09240_si_001.pdf (11.08 MB)
Highly Efficient Cascade Reaction for Selective Formation of Spirocyclobutenes from Dienallenes via Palladium-Catalyzed Oxidative Double Carbocyclization–Carbonylation–Alkynylation
journal contribution
posted on 2016-10-05, 00:00 authored by Youai Qiu, Bin Yang, Can Zhu, Jan-E. BäckvallA highly
selective cascade reaction that allows the direct transformation of
dienallenes to spirocyclobutenes (spiro[3.4]octenes) as single diastereoisomers
has been developed. The reaction involves formation of overall four
C–C bonds and proceeds via a palladium-catalyzed oxidative
transformation with insertion of olefin, olefin, and carbon monoxide.
Under slightly different reaction conditions, an additional CO insertion
takes place to give spiro[4.4]nonenes with formation of overall five
C–C bonds.