Indium organometallics in transition metal-catalyzed cross-coupling reactions

Stereospecific Indium(III)‐Catalysed Tandem Cycloisomerization of Functionalized 1,6‐enynes: Scope and Mechanistic Insights

“…[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.…”

“…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]…”

One-Step Transformation of Aryl Diazonium Salts into Aryl Indium(III) Reagents

“…The indium­(I) bromide is readily prepared from indium metal and bromine, and organoindium compounds are known to have low toxicity . Several applications of organoindiums in organic synthesis have been reported, , with an emphasis on cross-coupling chemistry. , It should be noted that triarylindium reagents are known to react with diazonium salts at room temperature in the absence of catalyst affording azo compounds (Scheme D). Nevertheless, aryl indium dihalides (ArInX 2 ) are known to be less reactive than Ar 3 In as sources of the aryl group in transition metal catalyzed couplings .…”