Nickel-catalyzed reductive arylation of activated alkynes with aryl iodides

Abstract

The direct, regioselective, and stereoselective arylation of activated alkynes with aryl iodides using a nickel catalyst and manganese reductant is described. The reaction conditions are mild (40 °C in MeOH, no acid or base) and an intermediate organomanganese reagent is unlikely. Functional groups tolerated include halides and pseudohalides, free and protected anilines, and a benzyl alcohol. Other activated alkynes including an amide and a ketone also reacted to form arylated products in good yields.

Nickel-Catalyzed Hydroarylation of Alkynes under Reductive Conditions with Aryl Bromides and Water

“…Various transition metals including Cr, Mn, Fe, Co, Ni, Cu, Rh, and Pd have all been used as catalysts for alkene synthesis in this fashion. Frequently, an organometallic reagent containing Li, B, Mg, Zn, or Sn is added to the alkyne, although other reagents including carbon dioxide and organohalides can undergo addition as well if a stoichiometric reductant is included. Additionally, the modern chemical technology allows alkyne hydroarylation through the direct activation of C–H bonds …”

“…Three-component coupling reactions involving alkynes and organometallic reagents are more common with the second-row transition metals Rh − and Pd because less reactive organometallic reagents (such as boronic acids) will participate in transmetalation with these metals; the reagents responsible for transmetalation and electrophilic trapping are more likely to be compatible in the same reaction flask. Still, there are several interesting reports of three-component reactions that involve carbometalation across an alkyne catalyzed by first-row transition metals such as Co and Ni. ,,, …”

Highly Regioselective and E/Z-Selective Hydroalkylation of Ynone, Ynoate, and Ynamide via Photoredox Mediated Ni/Ir Dual Catalysis

“…Trisubstituted enones are versatile synthetic building blocks for the preparation of natural products and biologically active compounds. A variety of methods such as aldol reactions, olefination, cross-coupling, , Heck reactions, C–H activation, and the addition of organometallic reagents have been developed to synthesize trisubstituted enones. However, these approaches are less efficient in the aspects of atom and step economy.…”

Tandem Reactions of Ynones: via Conjugate Addition of Nitrogen‐, Carbon‐, Oxygen‐, Boron‐, Silicon‐, Phosphorus‐, and Sulfur‐Containing Nucleophiles

“…Weix and co‐workers reported a nickel‐catalyzed method for the preparation of alkenoates [Eq. (73‐1)].…”