Fig. 2. Constructing molecular complexity: spiro-fused heterocycles from simple starting materials.

a Preliminary results show the importance of ammonium salts as the partners of the nucleophile. b Control experiments shown that the allylic aryl ether 3 was formed in situ as important intermediate during the cascade procedure. c A S_N2’ substitution process was proposed for the first reaction step, followed by sequence palladium-catalyzed Heck reaction/C–H activation/Pd reductive elimination to provide the target product 4.