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Homoallenic alcohols are versatile building blocks to access complex molecules in synthetic chemistry. We present a protocol for accessing homoallenic alcohols by an allenyl radical-involved radical-polar crossover process. We describe steps for preparing solvents and the photoreactor and synthesizing 5-methyl-1-phenyl-3-tosylhexa-3,4-dien-1-ol 3 in 85% yield. In addition, 5-methyl-1-phenyl-3-tosylhexa-3,4-dien-1-ol 3 has been successfully synthesized in 2-mmol scale. This protocol is also applicable to the synthesis of homoallenic amides. For complete details on the use and execution of this protocol, please refer to Wei et al. (2023). 1 ., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

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., (© 2022 Wiley-VCH GmbH.)

Trisubstituted alkenes are important organic synthons and have broad applications in the synthesis of many pharmaceuticals and materials. The stereoselective synthesis of such compounds has long been a research focus for organic researchers. Herein, we report a three-component, reductive cascade, cross-coupling reaction for the arylalkylation of alkynes. A wide range of trisubstituted alkenes are obtained in good to high yields with excellent chemo- and stereoselectivity by switching between electrochemistry and photocatalysis. The E isomer of the product is obtained exclusively when the reaction is conducted with electricity and nickel, while the Z isomer is generated with high stereoselectivity when photo- and nickel dual catalysts are used. Moreover, photo-assisted electrochemically enabled nickel catalyzed protocol is demonstrated to selectively deliver Z-trisubstituted alkenes without the addition of photocatalysts., (© 2022. The Author(s).)

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., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Disclosed herein is a novel, metal-free synthesis of γ-lactams through the radical-mediated nitration-aminocarbonylation of unactivated olefins. The reaction is initiated by a nitro radical generated from the homolysis of tert-butyl nitrite. The intramolecular cyanamide serves as the aminocarbonylating reagent. This protocol offers an environment-benign method to produce the synthetically valuable nitromethyl substituted γ-lactams.

A palladium-catalyzed efficient synthesis of 5-methylisoxazoles via oxime-mediated functionalization of unactivated olefins is described. The reaction affords a variety of 5-methylisoxazoles in moderate to good yields. To further demonstrate the utility of the method, the rapid synthesis of valdecoxib and oxacillin is reported.

An annulation via tandem rhodium catalyzed C-H olefination of N-benzoylsulfonamides with internal olefins followed by C-N bond formation is disclosed. A N-substituted quaternary center is formed during the reaction thus providing efficient access to a series of 3,3-disubstituted isoindolinones., (This journal is © The Royal Society of Chemistry 2012)

A tandem C-H olefination/annulation sequence directed by N-acylsulfonamides affords a variety of isoindolinones. This transformation is compatible with aliphatic alkenes as well as conjugated alkenes. Notably, molecular oxygen can be used as the sole, eco-friendly oxidant.

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]

The difunctionalization of unsaturated bonds plays a vital role in the enrichment of molecular complexity. While various catalytic methods for alkene and alkyne difunctionalization have been developed in recent years, hetero‐functionalization the introduction of two different atoms has been less explored. This is mainly due to the challenges associated with achieving high chemo‐, regio‐, and stereoselectivity, especially when adding two similar atoms from the same group across unsaturated bonds. In this study, we describe a nickel‐catalyzed, three‐component reductive protocol for group 14 element hetero‐difunctionalization of 1,3‐enynes using electrochemistry. This new method is mild, selective, and general, allowing for the silyl‐, germanyl‐, and stannyl‐alkylation of enynes. Various chlorosilanes as well as chlorogermans, and chlorostannanes can be successfully used in combination with aryl/alkyl‐substituted 1,3‐enynes and primary, secondary, and tertiary alkyl bromides in the electroreductive coupling. [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]

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]

Precise stereocontrol of functionalized alkenes represents a long-standing research topic in organic synthesis. Nevertheless, the development of a catalytic, easily tunable synthetic approach for the stereodivergent synthesis of both E-selective and even more challenging Z-selective highly substituted 1,3-dienes from common substrates remains underexploited. Here, we report a photoredox and nickel dual catalytic strategy for the stereodivergent sulfonylalkenylation of terminal alkynes with vinyl triflates and sodium sulfinates under mild conditions. With a judicious choice of simple nickel catalyst and ligand, this method enables efficient and divergent access to both Z- and E-sulfonyl-1,3-dienes from the same set of simple starting materials. This method features broad substrate scope, good functional compatibility, and excellent chemo-, regio-, and stereoselectivity. Experimental and DFT mechanistic studies offer insights into the observed divergent stereoselectivity controlled by ligands. The stereoselective synthesis of 1,3-dienes represents a challenge in organic synthesis. Here, the authors report a ligand-controlled stereodivergent access to both Z- and E-sulfonyl-1,3-dienes via photoredox and nickel catalysis. [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]

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]

In the biosynthesis sterols an enzyme-catalyzed demethylation is achieved via a stepwise oxidative transformation of alcohols to olefins. The overall demethylation proceeds through two sequential monooxygenation reactions and a subsequent dehydroformylative saturation. To mimic the desaturation processes observed in nature, we have successfully integrated photoredox proton-coupled electron transfer (PCET) and cobaloxime chemistry for the acceptorless dehydrogenation of alcohols. The state-of-the-art remote and precise desaturation of ketones proceeds efficiently through the activation of cyclic alcohols using bond-dissociation free energy (BDFE) as thermodynamic driving force. The resulting transient alkoxyl radical allows C-C bond scission to generate the carbon-centered radical remote to the carbonyl moiety. This key intermediate is subsequently combined with cobaloxime photochemistry to furnish the alkene. Moreover, the mild protocol can be extended to desaturation of linear alcohols as well as aromatic hydrocarbons. Application to bioactive molecules and natural product derivatives is also presented. Dehydrogenative reactions can provide alkenes, which are among the most useful handles for synthetic organic chemists. Here the authors integrated photoredox proton-coupled electron transfer and cobaloxime chemistry for the acceptorless dehydrogenation of alkyl alcohols. [ABSTRACT FROM AUTHOR]

Metallaphoto-catalysis has been established as a robust platform for efficient construction of a range of chemical bonds. Moreover, transformation of native functionalities such as C(sp3)–H bonds to produce functional molecules represents one of the most attractive strategies in organic synthesis. Merging two powerful methodologies, metallaphoto-catalyzed benzylic and allylic C(sp3)–H bond functionalizations provide a series of general and mild approaches for diversification of alkylbenzenes and alkenes. [ABSTRACT FROM AUTHOR]

Disclosed herein is a novel radical-mediated intermolecular carboarylation of alkenes by cleaving inert C–O bonds. The strategically designed arylbenzothiazolylether diazonium salts are harnessed as dual-function reagents. A vast array of alkenes are proven to be suitable substrates. The benzothiazolyl moiety in the products serves as the formyl precursor, and the OH residue provides the cross-coupling site for further product elaboration, indicating the robust transformability of the products. [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]

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]

Free radical mediated alkylation of alkenes is a challenging and largely unmet goal. Disclosed here is a conceptually novel "polarity umpolung" strategy for radical alkylation of alkenes using a portfolio of easily accessed, difunctional alkylating reagents. This strategy is achieved by substituting inherently nucleophilic alkyl radicals with electrophilic sulfone‐bearing surrogates, thus inverting the usual mode of reactivity. Along with alkylation, either an heteroaryl or oximino group is concurrently incorporated into the alkenes by a consecutive docking and migration process, leading to valuable products. The reaction displays a broad functional‐group tolerance under mild reaction conditions. The protocol opens new vistas for the late‐stage modification of complex natural products and drug molecules containing alkene moieties. [ABSTRACT FROM AUTHOR]

The first electrochemical approach for nickel‐catalyzed cross‐electrophile coupling was developed. This method provides a novel route to 1,1‐diarylalkane derivatives from simple and readily available alkyl and aryl halides in good yields and excellent regioselectivity under mild conditions. The procedure shows good tolerance for a broad variety of functional groups and both primary and secondary alkyl halides can be used. Furthermore, the reaction was successfully scaled up to the multigram scale, thus indicating potential for industrial application. Mechanistic investigation suggested the formation of a nickel hydride in the electroreductive chain‐walking arylation, which led to the development of a new nickel‐catalyzed hydroarylation of styrenes to provide a series of 1,1‐diaryl alkanes in good yields under mild reaction conditions. [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]

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]

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 copper‐catalyzed protocol for heteroarylsilylation of unactivated olefins is disclosed herein. The addition of a silyl radical to an alkene triggers a subsequent intramolecular heteroaryl migration. Heteroaryl groups such as benzothiazolyl, thiazolyl, imidazolyl, and pyridyl showcase their migratory aptitudes. A variety of heteroaryl‐substituted alkyl silanes are readily generated in synthetically useful yields. [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 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]

Disclosed herein is a novel, redox-neutral protocol for the visible-light-induced radical alkynylation of unactivated olefins. The intramolecular migration of an alkynyl group, by cleaving an inert C−C σ bond, is realized for the first time. A wide range of synthetically useful trifluoroethylated linear alkynes are readily obtained under mild reaction conditions. [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]

An efficient synthesis of highly functionalized γ-hydroxybutenolides through BF3-catalyzed annulation of keto acids with alkynes is described. Many advantages such as the use of routine reagents, easy operation, and a 100% atom efficiency are demonstrated in the method. The reaction can be readily scaled up to gram quantities, offering good practicality. [ABSTRACT FROM AUTHOR]

Abstract: An efficient approach to a wide range of isoindolinones, including 3-monosubstituted and 3,3-disubstituted isoindolinones, from the annulation of N-benzoylsulfonamides with olefins and diazoacetate has been developed. The transformation is broadly compatible with both terminal and internal olefins. Moreover, diazoacetate is for the first time incorporated into an amide-directed C–H functionalization reaction. Specifically, the rhodium complex [{RhCl2Cp*}2] enables the in situ dimerization of diazoacetate in addition to its role in catalyzing C–H functionalization/cross-coupling. [Copyright &y& Elsevier]

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]

An abstract of the article "Combination of a Cyano Migration Strategy and Alkene Difunctionalization: The Elusive Selective Azidocyanation of Unactivated Olefins" by Zhen Wu, Rongguo Ren and Chen Zu is presented.

Herein we report a novel, general protocol for distal heteroaryl ipso-migration and its application to the elusive heteroarylation of unactivated alkenes. A set of nitrogen-containing heteroaryl groups showcase the migratory aptitude. This reaction provides a variety of fluoroalkyl functionalized heteroarenes under mild reaction conditions. This is the first report of a difunctionalization of unactivated alkenes with distal heteroaryl migration. [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]

A wide range of chlorinated and brominated isoxazolines is prepared through Pd-catalyzed cyclization of oxime substrates in the presence of CuCl2 or CuBr2. [ABSTRACT FROM AUTHOR]