“…[6] Along the years, its catalytic activity has been exploited as σ-acid in fundamental organic transformations such as carbonyl additions or Diels-Alder reactions, [5] but also as π-acid in the hydrofunctionalization of carbon-carbon unsaturated bonds, mainly alkynes. [6,7] As part of our long-term studies on indium chemistry, [8] we have already reported the use of indium(III) as catalyst in intramolecular alkyne hydroarylation, hydroalkoxylation and hydroamination reactions, and more recently in 1,5-enyne cycloisomerization reactions. [9] Among the different organic compounds amenable to be used in π-acid catalysis, metal-catalysed cycloisomerization reactions of 1,n-enynes provide an extraordinary platform to explore the versatility, regioand stereoselectivity of the methodology, and to access a valuable set of cyclic structures present in natural and synthetic products.…”