Related Experiment Video
Updated: Jul 3, 2026
12:27
Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
Acid-catalyzed C-H reductive elimination from Au(iii).
Yotam Ardon1, Michael R Gau1, Karen I Goldberg1
1Department of Chemistry, University of Pennsylvania 231 S 34th St Philadelphia PA 19104 USA kig@sas.upenn.edu.
Chemical Science
|July 2, 2026
Summary
This study reports a novel acid-catalyzed C-H reductive elimination from a gold(III) complex. The reaction mechanism involves acid participation beyond simple acid strength, revealing an unusual catalytic pathway.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Gold Chemistry
Background:
- Gold complexes are increasingly recognized for their catalytic potential in organic synthesis.
- C-H activation and functionalization remain a significant challenge in synthetic chemistry.
- Understanding reaction mechanisms is crucial for designing efficient catalytic systems.
Purpose of the Study:
- To investigate an unusual mode of C-H reductive elimination from a gold(III) complex.
- To elucidate the role of acid catalysts in promoting this transformation.
- To explore the mechanistic details of the observed C-H reductive elimination.
Main Methods:
- Synthesis and characterization of a gold(III) hydride complex, [(tBuPCP)AuIII-H]OTf.
- Catalytic reaction studies using triflic acid (HOTf) as an additive.
- Structural characterization of the gold(I) product, [(tBuP(C-H)P)AuI]OTf, via NMR spectroscopy and X-ray diffraction.
- Mechanistic experiments to probe the role of the acid catalyst.
Main Results:
- Successful promotion of formal C-H reductive elimination from the gold(III) complex upon addition of triflic acid.
- Characterization of the resulting gold(I) complex with a unique κ2(1,3-C6H4(CH2PtBu2)2) ligand.
- Observation that the reductive elimination exhibits a dependence on the acid catalyst identity, not solely explained by acid strength.
- Mechanistic data suggest a concerted mechanism involving participation of basic moieties on the acid catalyst.
Conclusions:
- An unusual acid-catalyzed C-H reductive elimination pathway from a gold(III) complex has been discovered.
- The reaction mechanism appears to involve a concerted process where the acid's basicity plays a role.
- This finding expands the understanding of gold-catalyzed transformations and C-H activation/elimination reactions.
Related Concept Videos
01:38Preparation of Amines: Reductive Amination of Aldehydes and Ketones
Carbonyl compounds and primary amines undergo reductive amination first to produce imines, followed by secondary amines in the same reaction mixture, using selective reducing agents like sodium cyanoborohydride or sodium triacetoxyborohydride. Reductive amination produces different degrees of substitution of amines depending on the starting amine substrate.
00:55Nitriles to Amines: LiAlH4 Reduction
Nitriles are reduced to amines in the presence of strong reducing agents like lithium aluminum hydride through a typical nucleophilic acyl substitution. The reaction requires two equivalents of the reducing agent. The reducing agent acts as a source of hydride ions.
As shown below, the mechanism involves three steps. Firstly, the hydride ion acting as a nucleophile attacks the nitrile carbon to form an anion. In the second step, a second equivalent of the hydride ion attacks the anion to...
As shown below, the mechanism involves three steps. Firstly, the hydride ion acting as a nucleophile attacks the nitrile carbon to form an anion. In the second step, a second equivalent of the hydride ion attacks the anion to...
01:20Amides to Amines: LiAlH4 Reduction
Amide reduction with strong reducing agents like lithium aluminum hydride proceeds through a nucleophilic acyl substitution to form amines. Primary, secondary, and tertiary amides yield primary, secondary, and tertiary amines, respectively.
Amide reduction requires two equivalents of the reducing agent, acting as a source of hydride ions. As shown in the figure, the reaction is initiated with a nucleophilic attack by the hydride ion at the carbonyl carbon to form a tetrahedral intermediate.
Amide reduction requires two equivalents of the reducing agent, acting as a source of hydride ions. As shown in the figure, the reaction is initiated with a nucleophilic attack by the hydride ion at the carbonyl carbon to form a tetrahedral intermediate.
01:16Amines to Alkenes: Hofmann Elimination
Alkenes can be obtained from amines via an E2 elimination. The amine is first converted into a good leaving group, such as a quaternary ammonium salt. This is accomplished by treating the amine with an excess of alkyl halide, which results in a halide salt. Next, the halide salt is transformed into a hydroxide salt that functions as a base to enable elimination.
Under thermal conditions, the hydroxide can abstract a proton from the β carbon; this generates an alkene with the simultaneous...
Under thermal conditions, the hydroxide can abstract a proton from the β carbon; this generates an alkene with the simultaneous...
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
Introduction
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.
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.
01:13Preparation of Amines: Reduction of Amides and Nitriles
Nitriles can be reduced to primary amines using reducing agents like lithium aluminum hydride or catalytic hydrogenation. The reduction introduces an amino group with an extra carbon in the skeleton. Nitriles are formed from the reaction between alkyl halides and sodium cyanide through the SN2 mechanism. Primary alkyl halides are the preferred substrates to prepare nitriles.
Amides can be reduced to primary, secondary, and tertiary amines using catalytic hydrogenation, active metals like Fe,...
Amides can be reduced to primary, secondary, and tertiary amines using catalytic hydrogenation, active metals like Fe,...