Palladium catalysed [3 + 2]-annulation reaction of vinylcyclopropanes with pentafulvenes: synthesis of polysubstituted spiro[4,4]nona-6,8-dienes

Abstract

An efficient preparation method for the multisubstituted spiro[4,4]nona-6,8-dienes has been developed via a palladium catalysed [3 + 2]-annulation reaction between vinylcyclopropanes and pentafulvenes. The highlight of this method is the interesting regioselectivity. Furthermore, the products could be converted into more complex polycyclic systems easily.