Related Experiment Video
Updated: Jan 11, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Continuous-Flow Electrochemistry Enables 1,2-Arylheteroarylation of Alkenes
Xiaohan Sun1, Fantao Meng1, Kun Xu1
1College of Chemistry and Life Science, Beijing University of Technology, Beijing 100124, People's Republic of China.
Abstract:
Despite its potential, the radical-mediated 1,2-arylheteroarylation of alkenes for constructing valuable 1,2-arylheteroaryl ethane motifs remains underdeveloped. We herein report an alternative continuous-flow electrochemical approach using alkenes, aryl bromides, and cyanopyridines as coupling partners. This method eliminates the need for sacrificial anodes, catalysts, or chemical oxidants, requires minimal electrolyte, and achieves high regioselectivity. Its utility is underscored by successful applications in the late-stage functionalization of bioactive molecules.
Related Concept Videos
Preparation of Alkynes: Alkylation Reaction
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.
Thermal Electrocyclic Reactions: Stereochemistry
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
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.
Alkynes 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.
Electrophilic Aromatic Substitution: Friedel–Crafts Alkylation of Benzene
Electrophilic Addition to Alkynes: Hydrohalogenation

