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This work showcases a novel visible‐light mediated allenylation protocol employing propargyl sulfides as a pioneering radical trapping methodology. A diverse array of substituted sulfonyl allenes were successfully synthesized under mild conditions with commendable levels of chemo‐ and regio‐selectivity. Mechanistically, this process entails the formation of sulfonyl radicals, their subsequent addition to alkynes, the subsequent elimination of S‐centered radicals, and Cl‐atom abstraction, thereby facilitating the propagation of this radical chain reaction. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis and characterization of various 1-thiaphenalene derivatives using a radical approach and photoredox catalysis. The reaction involves the intermolecular cyclization of 1-naphthalenesulfonyl chlorides and alkynes under mild conditions, resulting in high product diversity and broad functional-group tolerance. The authors provide a plausible reaction mechanism and experimental details for the synthesis of specific compounds, which were characterized using techniques such as NMR, HRMS, and IR spectroscopy. This information can be valuable for researchers studying these compounds or related topics. [Extracted from the article]

Radical difunctionalization of aliphatic alkynes provides direct access to valuable multi‐substituted alkenes, but achieving a high level of chemo‐ and stereo‐control remains a formidable challenge. Herein a novel photoredox neutral alkyne di‐functionalization is reported through functional group migration followed by a radical‐polar crossover and energy transfer‐enabled stereoconvergent isomerization of alkenes. In this sequence, a hydroxyalkyl and an aryl group are incorporated concomitantly into an alkyne, leading to diversely functionalized E‐allyl alcohols. The scope of alkynes is noteworthy, and the reaction tolerates aliphatic alkynes containing hydrogen donating C─H bonds that are prone to intramolecular hydrogen atom transfer. The protocol features broad functional group compatibility, high product diversity, and exclusive chemo‐ and stereoselectivity, thus providing a practical strategy for the elusive radical di‐functionalization of unactivated alkynes. [ABSTRACT FROM AUTHOR]

A novel photoredox‐neutral 1,2,5‐trifunctionalization of α‐hydroxyhexenoates is disclosed. The radical cascade proceeds via heteroaryl migration‐enabled alkene fluoroalkylheteroarylation and radical‐polar crossover deuteration, leading to functionalized α‐deuterated lactic acid derivatives. The reaction features mild photochemical conditions and provides an efficient approach for the synthesis of valuable deuterated molecules. [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]

A metal‐free deformylative Minisci‐type reaction is disclosed by using aliphatic aldehydes as alkyl radical precursors. The reaction proceeds via a sequence of hydrogen atom abstraction (HAA) from aldehyde and decarbonylation under mild photochemical conditions. The transformation offers many advantages including good regioselectivity, broad substrate scope, and easy operation. The reaction is also amenable to late‐stage functionalization of complex heteroarenes, and can be readily performed on gram scale. [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]

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]

N‐Fused heterocycles are of particular use and upmost importance in multiple fields. Herein, we disclose a conceptually new approach for the rapid assembly of N‐fused heteroarenes from alkenes. A portfolio of strategically designed heterocyclization reagents are readily prepared for the cascade reaction. A plethora of N‐fused heteroarenes including seven types of heterocyclic core are furnished. The protocol features a broad functional‐group compatibility and high product diversity, and provides a practical tool for late‐stage heteroarene elaboration. [ABSTRACT FROM AUTHOR]

Chemical transformations based on cascade reactions have the potential to simplify the preparation of diverse and architecturally complex molecules dramatically. Herein, we disclose an unprecedented and efficient method for the cross‐coupling of radical precursors, dienes, and electrophilic coupling partners via a photoredox‐ and nickel‐enabled cascade cross‐coupling process. The cascade reaction furnishes a diverse array of saturated carbo‐ and heterocyclic scaffolds, thus providing access to a quick gain in C−C bond saturation. [ABSTRACT FROM AUTHOR]

A radical‐mediated monofluoroalkylative alkynylation of alkenes is disclosed for the first time. The reaction demonstrates a remarkably broad substrate scope in which both activated and unactivated alkenes are suitable starting materials. The concurrent addition of an alkynyl and a monofluoroalkyl group onto an alkene proceeds through a docking–migration sequence, affording a vast array of valuable fluoroalkyl‐substituted alkynes. Many complex natural products and drug derivatives are readily functionalized, demonstrating that this method can be used for late‐stage alkynylation. [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]

A new protocol for the elusive cyanotrifluoromethylthiolation of unactivated olefins is described. A broad range of vicinal CF3S-substituted alkyl nitriles are furnished in good yields under mild reaction conditions. The intramolecular cyano migration strategy is harnessed for the trifluoromethylthiolation of alkenes for the first time, thus offering an efficient tool for the construction of alkyl trifluoromethylthioethers. [ABSTRACT FROM AUTHOR]

The direct functionalization of an aliphatic C-H bond within a complex molecule through a free-radical pathway is a valuable tool in synthetic chemistry. Herein, we developed an efficient transition-metal-free approach to generate Δ2-isoxazolines from oximes by radical-mediated C(sp3)-H oxidation. Investigation of the mechanism suggested that in the presence of Selectfluor and Bu4NI, the homolysis of the in situ formed O-I bond generated an iminoxyl radical that facilitated subsequent 1,5-H transfer and C(sp3)-H oxidation. [ABSTRACT FROM AUTHOR]

Review: [20 refs. [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]