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A new cross‐coupling of trifluoromethyl arenes has been realized via multiphoton photoredox catalysis. Trifluoromethyl arenes were demonstrated to undergo selective mono‐defluorinative alkylation under mild reaction conditions providing access to a series of valuable α,α‐difluorobenzylic compounds. The reaction shows broad substrate scope and general functional group tolerance. In addition to the electron‐deficient trifluoromethyl arenes that are easily reduced to the corresponding radical anion, more challenging electron‐rich substrates were also successfully applied. Steady‐State Stern‐Volmer quenching studies indicated that the trifluoromethyl arenes were reduced by the multiphoton excited Ir‐based photocatalyst. [ABSTRACT FROM AUTHOR]

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]

Alkenes, in particular, low-boiling-point alkenes such as ethylene, are bulk chemical materials in the petrochemical industry. Conversion of these inexpensive materials to value-added fine chemicals is of utmost importance. Herein, we report an efficient approach for radical alkylfunctionalization of gaseous ethylene and other light alkenes by remote functional group migration. Various alkyls including deuterated alkyl groups are readily incorporated into alkenes along with the installation of extra heteroaryl or oximino groups, leading to complex functionalized alkanes. This photochemical method is operationally simple, proceeding even in the absence of photosensitizers and transition-metal additives. [ABSTRACT FROM AUTHOR]

Herein, we disclose a novel self-catalytic photochemical sulfonylation of phenothiazines, in which phenothiazine functions as both a substrate and a photosensitizer. The reaction proceeds under visible-light irradiation without an extra photocatalyst and additives and presents a green synthetic approach to access valuable mono- and di-sulfonylated phenothiazines. This late-stage modification process massively enriches the library of phenothiazine-based organophotocatalysts and features operational simplicity, broad functional group compatibility, and high product diversity. [ABSTRACT FROM AUTHOR]

Disclosed herein is the first example of radical-mediated remote migration of quinoxalinones. The quinoxalinonyl-functionalization of alkenes employs the quinoxalinone-substituted tertiary bishomoallylic alcohols as substrates, proceeds through intramolecular 1,4-quinoxalinone migration, and gives rise to complex γ-quinoxalinone-substituted aliphatic ketones. A set of external radicals is compatible with this method. The protocol features broad tolerance of functional groups, good adaptability to various external radicals and high product diversity, and opens a new door for the synthesis of quinoxalinone derivatives. [ABSTRACT FROM AUTHOR]

The nickel‐catalyzed three‐component reductive carbonylation of alkyl halides, aryl halides, and ethyl chloroformate is described. Ethyl chloroformate is utilized as a safe and readily available source of CO in this multi‐component protocol, providing an efficient and practical alternative for the synthesis of aryl‐alkyl ketones. The reaction exhibits a wide substrate scope and good functional group compatibility. Experimental and DFT mechanistic studies highlight the complexity of the cross‐electrophile coupling and provide insight into the sequence of the three consecutive oxidative additions of aryl halide, chloroformate, and alkyl halide. [ABSTRACT FROM AUTHOR]

We report a novel asymmetric radical cyclization of alkenes via stereospecific homolytic substitution of sulfinamides. This reaction produces a variety of cyclic sulfinamides with excellent stereocontrol. The protocol features broad functional group tolerance, high product diversity, and easy accessibility to feedstocks, and outlines a new pathway for the synthesis of chiral cyclic sulfinamides. [ABSTRACT FROM AUTHOR]

Practical, metal-free heteroarylations of C–H and C–C bonds of unprotected aliphatic alcohols are accomplished in a 'stop-flow' micro-tubing reactor. The reactions proceed through alkoxy radical-triggered hydrogen atom transfer and β-C(sp3)–C(sp3) bond rupture under mild photochemical conditions, leading to a plethora of valuable functionalized heteroarenes. The reaction is amenable for late-stage functionalization of complex heteroarenes, and can be readily scaled up by a continuous-flow method. The protocol features many advantages including good regioselectivity, broad functional group compatibility, and easy operation, and may find potential use in medicinal chemistry. [ABSTRACT FROM AUTHOR]

A novel radical-mediated trifunctionalization of hexenenitriles via the strategy of remote functional group migration is disclosed. A portfolio of functionalized hexenenitriles are employed as substrates. After difunctionalization of the unactivated alkenyl part via remote cyano migration, the in situ formed radical intermediate is captured by an azido radical, thus enabling the trifunctionalization. The reaction features mild conditions and broad functional group compatibility, leading to valuable products bearing multiple useful groups. This protocol further extends the scope of remote functional group migration. [ABSTRACT FROM AUTHOR]

Rearrangement reactions, one of the most significant transformations in organic chemistry, play an irreplaceable role in improving synthetic efficiency and molecular complexity. Concomitant cleavage and reconstruction of chemical bonds can display the great artistry and the glamour of synthetic chemistry. Over the past century, ionic rearrangement reactions, in particular those involving cationic pathways, have represented most of the research. Alongside the renaissance of radical chemistry, radical-mediated rearrangements have recently seen a rapid increase of attention from the chemical community. Many new radical rearrangements that extensively reveal the migratory behaviour of functional groups have been unveiled in the last decade. This Review provides a comprehensive perspective on the area from the past to present achievements, and brings up the prospects that may inspire colleagues to develop more useful synthetic tools based on radical rearrangements. [ABSTRACT FROM AUTHOR]

The construction of multiply functionalized bicyclo[1.1.1]pentanes (BCPs) is of high synthetic value, as they are frequently harnessed as bioisosteres of 1,3-disubstituted benzene rings, alkynes, and tert -butyl groups in medicinal chemistry. Herein, we disclose a practical radical-mediated carbosulfonylation of propellane for the synthesis of sulfonyl β-keto-substituted BCPs by using vinyl sulfonates as dual-function reagent. This protocol features broad functional group tolerance and excellent atom-economy, leading to a variety of valuable difunctionalized BCP derivatives under mild photochemical conditions. [ABSTRACT FROM AUTHOR]

Regioselective incorporation of a particular functional group into aliphatic sites by direct activation of unreactive C−H bonds is of great synthetic value. Despite advances in radical‐mediated functionalization of C(sp3)−H bonds by a hydrogen‐atom transfer process, the site‐selective vinylation of remote C(sp3)−H bonds still remains underexplored. Reported herein is a new protocol for the regioselective vinylation of unactivated C(sp3)−H bonds. The remote C(sp3)−H activation is promoted by a C‐centered radical instead of the commonly used N and O radicals. The reaction possesses high product diversity and synthetic efficiency, furnishing a plethora of synthetically valuable E alkenes bearing tri‐/di‐/mono‐fluoromethyl and perfluoroalkyl groups. Give and take: Regioselective incorporation of a particular functional group into aliphatic sites by direct activation of unreactive C−H bonds remains challenging. Herein a new protocol for the regioselective vinylation of unactivated C(sp3)−H bonds is reported. The activation of a remote C(sp3)−H bond is promoted by a C‐centered radical instead of the commonly used N and O radicals. [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]

Aryl and heteroaryl boronic acids and boronate esters are rapidly, often within minutes, transformed into the corresponding phenols by N-oxides in an open flask at ambient temperature. This transformation has broad compatibility with a variety of functional groups. [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]

Bicyclo[1.1.1]pentane is widely recognized as the bioisostere for aryl, tert-butyl, and internal alkynes. Herein we report an efficient and practical method for the preparation of selenoether and thioether functionalized bicyclo[1.1.1]pentanes from selenosulfonates/thiosulfonates and propellane. A variety of valuable bicyclo[1.1.1]pentanes bearing both selenoether/thioether and sulfone are obtained under mild conditions with good yields. The protocol features broad functional group compatibility, excellent atom-economy, simple operation, and gram-scale preparation. Image 1 [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]