A metal-free addition/dearomatization–cyclization/decarboxylation cascade of aryl 3-arylpropiolate toward the synthesis of 1,1-diaryl-2-alkyl-substituted ethylenes

Radical Rearrangement Reaction of Propargyl Ethers to α,β-Unsaturated Aldehydes via Photoredox and Ni Catalysis

Aryl migration, especially 1,4-aryl migration, is one of the most important reactions in radical rearrangement. Over the past decades, 1,4-aryl migration by the addition of a radical to alkynes has become a simple and efficient method in the difunctionalization reactions of alkynes. Radical-based 1,4-aryl migration of aryl alkynoates has been well-explored; however, the 1,4-aryl migration of aryl propynyl ethers is rarely studied. Herein, we first described radical 1,4-aryl migration of propargyl ether to valuable α,β-unsaturated aldehydes via photoredox and Ni catalysis. This method features redox-neutral conditions, readily available starting materials, broad substrate scope, good functional group compatibility, and diverse transformations. Mechanistic studies suggest that this reaction proceeds through a radical-involved pathway.

Synthesis of tri-substituted allyl alcohols via a copper/iron co-catalyzed cascade perfluoroalkylation/rearrangement of aryl propynyl ethers

A copper/iron co-catalyzed fluoroalkylation of aryl propynyl ethers for the synthesis of perfluoroalkylated tri-substituted allyl alcohol derivatives is reported.

Recent advances in radical transformations of internal alkynes

This review highlights the recent progress in the radical transformation of internal alkynes and focuses on the reaction mechanisms by carbon/heteroatom-centered triggered additions, and offers a comprehensive overview on the existing procedures and employed methodologies.

Catalyst-free synthesis of α-thioacrylic acids via cascade thiolation and 1,4-aryl migration of aryl alkynoates at room temperature

A simple and facile catalyst-free strategy has been developed for the synthesis of α-thioacrylic acids from readily-available aryl alkynoates and thiols at room temperature under air.

Recent Advances in Radical C-H Activation/Radical Cross-Coupling

Research and industrial interest in radical C-H activation/radical cross-coupling chemistry has continuously grown over the past few decades. These reactions offer fascinating and unconventional approaches toward connecting molecular fragments with high atom- and step-economy that are often complementary to traditional methods. Success in this area of research was made possible through the development of photocatalysis and first-row transition metal catalysis along with the use of peroxides as radical initiators. This Review provides a brief and concise overview of the current status and latest methodologies using radicals or radical cations as key intermediates produced via radical C-H activation. This Review includes radical addition, radical cascade cyclization, radical/radical cross-coupling, coupling of radicals with M-R groups, and coupling of radical cations with nucleophiles (Nu).

Metal-Free Cascade Oxidative Decarbonylative Alkylation/Arylation of Alkynoates with Alphatic Aldehydes

The oxidative difunctionalization of aryl alkynoates with alphatic aldehydes as a cheap and abundant alkyl radical source was developed, providing a variety of trisubstituted alkenes in moderate to good yields. In this reaction, radical decarbonylative alkylation of C-C triple bond, 1,4-aryl migration, and decarboxylation were involved under metal-free conditions.

Transition metal-free decarboxylative alkylation reactions

This review summarizes recent advances in the transition metal-free decarboxylative alkylation of carboxylic acids and their derivatives.