Related Experiment Video
Updated: May 23, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Metal-Catalyzed Reductive Coupling of Aryl Halides beyond Premetalated Reagents or Metallic Reductants: Biaryl
Yoon Cho1, Yu-Hsiang Chang1, Weijia Shen1
1Department of Chemistry, University of Texas at Austin, Welch Hall (A5300), 105 E 24th St., Austin, Texas 78712, United States.
Abstract:
Biaryl motifs figure prominently in commercial pharmaceutical and agrochemical ingredients and are used widely in organic optoelectronic materials. Traditional palladium-catalyzed cross-coupling reactions, such as Suzuki, Negishi and Stille couplings, are powerful methods for aryl-aryl bond formation, but their reliance on premetalated reagents poses practical limitations. As most arylmetal reagents derive from the corresponding aryl halides, considerable effort has been devoted to the development of direct catalytic aryl halide reductive couplings. However, most methods require metallic reductants. In this monograph, metal-catalyzed aryl halide reductive homocouplings (Ullmann reactions) and cross-couplings mediated by nonmetallic reductants are surveyed.
Related Concept Videos
Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction
Nucleophilic Aromatic Substitution: Elimination–Addition
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
Acid Halides to Ketones: Gilman Reagent
As shown below, the mechanism proceeds in two steps. First, one of the alkyl groups of the reagent acts as a nucleophile and attacks the acyl carbon of the acid chloride to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen double...
Acid Halides to Alcohols: Grignard Reaction
Grignard reagents are a source of carbanions and function as nucleophiles. The mechanism begins with the nucleophilic attack by the carbanion at the carbonyl carbon of the acid halide to form a tetrahedral intermediate. Next, the carbonyl group is re-formed, and the halide ion departs,...
