A combined mechanistic and computational study of the gold(I)-catalyzed formation of substituted indenes

Substituted indenes can be prepared after a sequence [1,3] O-acyl shift-hydroarylation-[1,3] O-acyl shift. Each step is catalyzed by a cationic NHC-Gold(I) species generated in situ after reaction between [(IPr) AuOH] and HBF4 center dot OEt2. This interesting silver-free way is fully supported by a computational study justifying the formation of each intermediate.