Related Experiment Video
Updated: Sep 9, 2025
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Organic Photoredox Catalytic Functionalization of Alkynones To Acess Heterocycles Containing 1,4-Dicarbonyl
Ying Zhou1, Jun Sun1, Jintong Xie1
1Zhejiang Key Laboratory of Green Manufacturing Technology for Chemical Drugs, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
Abstract:
Herein, we report an efficient visible-light-mediated reaction of alkynones with ethyl diazoacetate for the construction of cyclic frameworks containing the 1,4-dicarbonyl moiety. In this photocatalytic system, a readily available phenothiazine derivative serves as the organic catalyst, which, upon photoexcitation, gains strong reducing power to facilitate the divergent synthesis of structurally diverse thioflavone derivatives. This metal-free protocol exhibits broad substrate scope and mild reaction conditions, providing a versatile and sustainable approach to high-value heterocycles.
More Related Videos
09:12[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
06:34Synthesis of Antiviral Tetrahydrocarbazole Derivatives by Photochemical and Acid-catalyzed C-H Functionalization via Intermediate Peroxides CHIPS
Published on: June 20, 2014
Related Concept Videos
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
Photochemical Electrocyclic Reactions: Stereochemistry
Selection Rules: Photochemical Activation
Cycloaddition Reactions: MO Requirements for Photochemical Activation
Cycloaddition Reactions: Overview
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.
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide