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Fluorine incorporation by concomitant fluoroalkyl radical addition to alkene or alkyne and functional group migration (FGM) represents an ingenious and robust strategy for the synthesis of structurally diverse fluorinated compounds. This account gives an overview of related studies in our group, in which three main reaction modes are discussed: 1) radical fluoroalkylative difunctionalization of unactivated alkenes via intramolecular FGM; 2) alkene difunctionalization by docking‐migration process using fluoroalkyl‐containing bifunctional reagents; 3) incorporation of fluoroalkyl group into C(sp3)−H bond via consecutive hydrogen atom transfer (HAT) and FGM. Relying on these methods, a variety of trifluoromethylation and di‐/mono‐fluoroalkylation reactions along with the migration of cyano, heteroaryl, oximino, formyl, alkynyl, and alkenyl groups have been accomplished under mild conditions. [ABSTRACT FROM AUTHOR]

Heteroarenes are important units in organic chemistry and are ubiquitous in natural products, pharmaceuticals, and numerous artificial molecules. Despite great efforts devoted to accessing heteroarenes, the development of new methods to efficiently produce heteroarenes remains a long-term interest. Recently, the strategy of radical-mediated heteroaryl migration has supplied a robust toolkit for the synthesis of a diversity of heteroaryl-containing compounds. This Account summarizes our recent achievements in this field and provides insight into the incorporation of heteroarenes into organic skeletons. 1 Introduction 2 Radical-Mediated Heteroarylation of Alkanes and Alkenes via Intramolecular Heteroaryl Migration 2.1 C(sp3)–H Heteroarylation via Intramolecular Heteroaryl Migration 2.2 Difunctionalization of Alkenes via Intramolecular Heteroaryl Migration 3 Intermolecular Difunctionalization of Alkenes via 'Docking-Migration' Strategy 3.1 Sulfone-Based Bifunctional Reagents for Difunctionalization of Alkenes by Docking Migration 3.2 Sulfone-Based Reagents for the Synthesis of N-Fused Heteroarenes by Docking Migration 3.3 Tertiary Alcohol Based Bifunctional Reagents for Difunctionalization of Alkenes by Docking Migration 3.4 Diaryl Ether Based Bifunctional Reagents for Difunctionalization of Alkenes by Docking Migration 3.5 Conclusion [ABSTRACT FROM AUTHOR]

Radical‐mediated difunctionalization of alkenes provides a promising approach to introduce one alkenyl or alkynyl group to target compounds. However, simultaneous installation of two unsaturated C−C bonds via alkene difunctionalization remains elusive, attributable to the high instability and transient lifetimes of alkenyl and alkynyl radicals. Herein, we report the photocatalytic 1,2‐alkynylalkenylation and 1,2‐enynylalkenylation of alkenes for the first time, triggered by the intermolecular addition of a stabilized allenyl radical to an alkene. A portfolio of strategically designed, easily accessible dual‐function reagents are applied to a radical docking‐migration cascade. The protocol has broad substrate scope and efficiently increases the degree of unsaturation. [ABSTRACT FROM AUTHOR]

A radical-mediated hetaryl functionalization of nonactivated alkenes through distal ipso -migration of O- or S-containing hetaryls was developed. Furyl, benzofuryl, thienyl, and benzothienyl groups showed satisfactory migratory abilities. A variety of heteroatom-centered radicals, including azido, trifluoromethylsulfanyl, and silyl radicals readily trigger the migration cascade, and a new C–heteroatom and C–C bond are concomitantly constructed in the reaction. This method provides an efficient approach to the synthesis of high-valued complex O- or S-hetaryl compounds. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: A novel, rational‐designed approach to access various heteroaryl‐substituted alkyl thioethers was developed via docking‐migration cascade process. By utilizing three components involving alkene, dual‐function reagent, and thioetherificating reagent, radical heteroarylalkylation of alkenes followed by thiolation of the alkyl radical intermediates proceeded smoothly, manifesting well compatibility of substrates and cascade transformations. Furthermore, this protocol also features mild conditions, broad substrate scope, and wide product diversity. [ABSTRACT FROM AUTHOR]

Radical‐mediated difunctionalization of alkenes is a powerful tactic for olefin utilization. However, the transformation of unactivated alkenes still remains a formidable challenge. Now a conceptually new docking–migration strategy is presented for the difunctionalization of alkenes with photoredox catalysis. Both activated and unactivated alkenes are suitable substrates. A vast array of functional groups are compatible with the mild reaction conditions. Heteroaryl and difluoromethyl are concomitantly incorporated into alkenes, leading to synthetically valuable products that are readily converted into a variety of fluorine‐containing molecules. The protocol provides a kinetic control of stereoselectivity for cycloalkenes to generate the unusual cis‐products, and offers an efficient approach for the late‐stage functionalization of complex natural products and drug molecules. A portfolio of dual‐function reagents are prepared for the elusive radical difunctionalization of alkenes. All aboard: A conceptually new docking–migration strategy for the difunctionalization of alkenes under visible‐light photoredox catalysis is disclosed. Both activated and unactivated alkenes are suitable substrates. A vast array of functional groups are compatible with the mild reaction conditions. [ABSTRACT FROM AUTHOR]

Abstract: A general and practical protocol for elusive carbo‐difluoroalkylation/ monofluoroalkylation of unactivated alkenes based on the distal functional group migration is described. A portfolio of functional groups including heteroaryl, imino, formyl, and alkynyl groups showcase the migratory aptitude. In combination with visible‐light photocatalysis, a broad range of di‐ and mono‐fluorinated alkyl ketones are readily obtained in synthetically useful yields under mild reaction conditions. [ABSTRACT FROM AUTHOR]

A general protocol for the challenging cyanofluoroalkylation of unactivated alkenes is disclosed. A broad range of synthetically useful di- and mono-fluorinated alkyl nitriles are readily obtained in good yields under mild reaction conditions. The efficient combination of intramolecular cyano migration and photoredox catalysis significantly expands the field of difunctionalization of olefins. [ABSTRACT FROM AUTHOR]

A conceptually new, efficient, and metal-free approach for the challenging azidocyanation of unactivated alkenes is presented. The strategy of intramolecular distal cyano migration is combined with alkene difunctionalization for the first time. A variety of useful azido-substituted alkyl nitriles are prepared in good yields and, most importantly, with exquisite regio- and stereo-selectivities. [ABSTRACT FROM AUTHOR]

Chen Zhu: (left) received his B.S. degree from Xiamen University in 2003 under the supervision of Prof. Pei-Qiang Huang, and his Ph.D. degree from the Shanghai Institute of Organic Chemistry in 2008 under the supervision of Prof. Guo-Qiang Lin. After postdoctoral research at -Gakushuin University, Japan with Prof. Takahiko Akiyama, he moved to the University of Texas Southwestern Medical Center, working as a postdoctoral fellow with Prof. John R. Falck and Prof. Chuo Chen. He was appointed as a professor at Soochow University, China in December 2013. He is currently the Head of the Organic Chemistry Department at Soochow University. His current research interests include radical-mediated transformations, in particular radical -rearrangements, and their applications in the construction of natural products and biologically active compounds. Xin-Yuan Liu (right) obtained his B.S. degree from Anhui Normal University (AHNU) in 2001. He continued his research studies at both the Shanghai Institute of Organic Chemistry (SIOC), CAS and AHNU under the joint supervision of Prof. Dr. Shizheng Zhu and Prof. Dr. Shaowu Wang, obtaining his master's degree in 2004. After a one-year stint in Prof. Gang Zhao's laboratory at SIOC, he joined Prof. Dr. Chi-Ming Che's group at The University of Hong Kong (HKU) and earned his Ph.D. degree in 2010. He subsequently undertook postdoctoral studies in Prof. Che's group at HKU and in Prof. Carlos F. Barbas III's group at The Scripps Research Institute. At the end of 2012, he began his independent academic career at the Southern University of Science and Technology (SUSTech) and was promoted to a tenured Full Professor of SUSTech in 2018. His research interests are directed towards the design of novel chiral anionic ligands to solve radical-involved asymmetric reactions. [ABSTRACT FROM AUTHOR]

Radical-mediated controllable difunctionalization of alkenes provides a powerful tool for the manipulation of olefins and has become a hot topic recently. In general, however, the scope of alkene is largely restricted to the activated alkenes. The development of a general strategy for the functionalization of unactivated alkenes is desired, yet remains challenging. In this review, we have summarized the recent advances in the strategy of intramolecularly distal migration of functional groups which has been efficiently applied in the radical-mediated difunctionalization of unactivated alkenes. A portfolio of functionalities including aryl, cyano, heteroaryl, imino, carbonyl, alkynyl, and alkenyl groups showcase the migratory aptitude. [ABSTRACT FROM AUTHOR]

Abstract An efficient visible-light photocatalytic protocol for the vicinal heteroarylsulfonylation and oximinosulfonylation of unactivated olefins is described. The addition of sulfonyl radicals to alkenes triggers the intramolecular migration of remote heteroaryl and oximino groups via C C bond cleavage. The transformation features a good functional group tolerance and a broad substrate scope. A variety of valuable heteroaryl- and oximino-substituted alkyl sulfones are obtained under mild conditions in synthetically useful yields. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

We report a new reaction mode involving functional group migration, which is applied to the radical-mediated remote desaturation of hexenenitriles. The reaction proceeds through consecutive alkene sulfonylation, intramolecular cyano migration, and single-electron oxidation of benzyl radical to cation followed by deprotonation, leading to a variety of densely functionalized alkenes. The protocol features mild photocatalytic conditions, broad functional group tolerance, and high product diversity. [Display omitted] [ABSTRACT FROM AUTHOR]

• Novel approach for radical-mediated trifluoromethylative aminocarbonylation of unactivated olefins. • The reaction features mild conditions, good functional group tolerance, and broad substrate scope. • The CF 3 -functionalized γ-lactam products are synthetically valuable. An efficient approach for the synthesis of γ-lactams through radical-mediated trifluoromethylative aminocarbonylation of unactivated olefins is described. The transformation is initiated by the addition of an external CF 3 radical to alkene followed by interception with intramolecular cyanamide. This protocol provides a useful method to furnish the synthetically valuable CF 3 -functionalized γ-lactams. [ABSTRACT FROM AUTHOR]