Gold-catalyzed four-component multifunctionalization of alkynes
Shangwen Fang1, Jie Han1, Chengjian Zhu1,2
1State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, 210023, Nanjing, China.
Nature Communications
|June 15, 2023
Summary
This study introduces a novel gold-catalyzed reaction for multifunctionalizing alkynes, creating four new bonds. The reaction
Area of Science:
- Organic Synthesis
- Catalysis
- Medicinal Chemistry
Background:
- Alkynes are crucial building blocks in organic synthesis.
- Developing selective multifunctionalization methods for alkynes is a key research area.
- Existing methods often lack efficiency or selectivity in complex transformations.
Purpose of the Study:
- To report a novel gold-catalyzed four-component reaction for alkyne transformation.
- To achieve selective oxo-arylfluorination or oxo-arylalkenylation of internal alkynes.
- To demonstrate reaction divergence control based on directing functional groups.
Main Methods:
- Utilized a gold(I)/gold(III) redox catalysis cycle.
- Employed Selectfluor as both an oxidant and a fluorinating reagent.
- Investigated the influence of phosphonate and carboxylate directing groups on reaction outcome.
Main Results:
- Efficiently broke the alkyne carbon-carbon triple bond, forming four new chemical bonds.
- Achieved site-directing control for oxo-arylfluorination (phosphonate) and oxo-arylalkenylation (carboxylate).
- Synthesized diverse α,α-disubstituted ketones and unsaturated ketones with high yields and selectivity.
Conclusions:
- The developed gold-catalyzed reaction offers a versatile route to complex ketones.
- The reaction demonstrates excellent control over selectivity through directing groups.
- Gram-scale synthesis and late-stage functionalization highlight practical synthetic utility.
More Related Videos
Related Concept Videos
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
7.8K
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.
7.8K
02:27Preparation of Alkynes: Alkylation Reaction
10.3K
Introduction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
10.3K
02:47Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
18.4K
Introduction
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.
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.
18.4K
02:38Electrophilic Addition to Alkynes: Halogenation
8.3K
Introduction
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
8.3K
02:34Preparation of Alkynes: Dehydrohalogenation
16.0K
Introduction
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.
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.
16.0K
02:40Alkynes to Aldehydes and Ketones: Acid-Catalyzed Hydration
8.6K
Introduction
Analogous to alkenes, alkynes also undergo acid-catalyzed hydration. While the addition of water to an alkene gives an alcohol, hydration of alkynes produces different products such as aldehydes and ketones.
Analogous to alkenes, alkynes also undergo acid-catalyzed hydration. While the addition of water to an alkene gives an alcohol, hydration of alkynes produces different products such as aldehydes and ketones.
8.6K