Related Experiment Video
Updated: Jan 8, 2026
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Iridium-Catalyzed γ-Hydro(hetero)arylation of α,β-Unsaturated Amides
Shoki Asai1, Yuta Akahori1, Yasuharu Yoshimi1
1Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui-shi, Fukui 910-8507, Japan.
Abstract:
α,β-Unsaturated amides are versatile building blocks in organic synthesis; however, forging C-C bonds at the γ-position is considerably more challenging than conventional β-addition. Herein, we report an iridium-catalyzed γ-hydro(hetero)arylation of α,β-unsaturated amides that delivers γ-adducts with high regioselectivity. Mechanistic experiments support an initial alkene isomerization to a β,γ-unsaturated intermediate, followed by γ-selective hydro(hetero)arylation. The coordinating amide functionality is essential for both reactivity and selectivity, enabling reactions with indoles and an electron-rich arene.
More Related Videos
Related Concept Videos
02:47Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
00:51Base-Promoted α-Halogenation of Aldehydes and Ketones
01:21Acid-Catalyzed α-Halogenation of Aldehydes and Ketones
In the first step of the mechanism, the acid protonates the carbonyl oxygen resulting in a resonance-stabilized cation, which subsequently loses an α-hydrogen to form an enol tautomer. The C=C bond in an enol is highly nucleophilic because of the electron-donating nature of the –OH group. Consequently, the double bond attacks an electrophilic halogen to form a...
01:28Preparation of 1° Amines: Gabriel Synthesis
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
02:36Regioselectivity and Stereochemistry of Hydroboration
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
02:34Preparation of Alkynes: Dehydrohalogenation
Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.