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Abstract: The Zr-catalyzed methylalumination of heterosubstituted arylethynes containing O, S, Cl, and Si can proceed in high yields (>70%) and in a highly regio- and stereoselective manner (⩾98–99%), although SO2Ph, Br, and Cl in a benzylic position present serious chemoselectivity-related problems. The low regioselectivity of 60% initially observed with o-ethynylphenol (1a) has been elevated to ⩾98% through the use of either a catalytic amount of Zr(ebi)Cl2 or Zr(2-Me-Ind)2Cl2 or, more conveniently, the stoichiometric amount of ZrCp2Cl2, ZrCp2MeCl, or ZrCp2Me2 in conjunction with the use of a deficient amount (0.9molar equiv.) of I2 for subsequent iodinolysis. [Copyright &y& Elsevier]

Comprehensive Summary: A visible light photocatalytic [3+2] cycloaddition of alkynes with readily accessible organic iodides as the C3 synthon is developed herein. By merging halogen atom transfer (XAT) and hydrogen atom transfer (HAT), alkyl/aryl iodides serve as a formal diradical precursor and add across C‐C triple bonds to deliver a number of functionalized cyclopentanes in moderate to high yields with exceptional regio‐ and diastereoselectivity. A reductive radical‐polar crossover mechanism, involving the cascade XAT, radical addition, 1,5‐HAT, polar effect‐promoted 5‐endo annulation, single electron transfer (SET) reduction, and protonation, may account for this unprecedented dehalogenative [3+2] cycloaddition. This work not only expands the repertoire of the traditional RATC methodology, but also provides a robust platform for the expedient assembly of cyclopentanes, a valuable structural motif in the realms of medicinal chemistry and material sciences. [ABSTRACT FROM AUTHOR]

5-endo-trig radical cyclization has long been recognized as one of the most straightforward ways for the construction of densely functionalized five-membered rings. Nevertheless, according to Baldwin's rules, the 5-endo-trig radical cyclization is kinetically disfavored due to stereoelectronic effects and thus usually proceeds via a slow rate, which renders its application a challenging task. In recent years, with the emergence of efficient radical generation methods and effective cyclization strategies, 5-endo-trig radical cyclization has been successfully accelerated to a synthetically useful rate and has been utilized in the access of diverse five-membered carbo- and heterocyclic compounds. This review comprehensively summarizes the methodologies involving the 5-endo-trig radical cyclization process, with particular emphasis on the elucidation of the promoting strategies, which include the polar effect, geometrical constraints, spin delocalization effect, and persistent radical effect. Each of these strategies is discussed in detail, with illustrative examples from recent literature studies to highlight their practical applications and effectiveness. It is anticipated that the in-depth understanding of the 5-endo-trig radical cyclization provided by this review would inspire further innovation of this privileged reaction mode and expand its applications. Moreover, the potent ring-closure-promoting strategies revealed herein would also contribute to achieving other challenges of cyclizations with particular significance for organic synthesis. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Compared to well‐established 1,5‐HAT of N‐centered radicals, the synthetic applications of 1,2‐HAT process were scarce due to the high barrier and constrained three‐membered transition state. Here, we have developed a novel C(sp3)‐H gem‐difluoroallylation via a base assisted formal 1,2‐HAT of amidyl radicals with the reductive quenching cycle of photocatalyst. This transformation enables the efficient formation of α‐aminoalkyl radicals via 1,2‐HAT and showcases good functional group tolerance. Our preliminary mechanistic experiments, along with Density Functional Theory (DFT) calculations demonstrate the feasibility of 1,2‐HAT of amidyl radicals, especially when assisted by a base. Furthermore, our method also succeeds in the Giese addition of electron‐deficient alkenes as well as styrene. [ABSTRACT FROM AUTHOR]

Cyclobutanes are popular structural units in bioactive compounds and versatile intermediates in synthetic chemistry, but their synthesis is challenging owing to high ring strain. In this study, a novel method for highly regio‐ and diastereoselective synthesis of fluoroalkylcyclobutanes bearing vicinal quaternary and tertiary stereocenters is realized by a photocatalytic 4‐exo‐trig cyclization cascade of thioalkynes or trifluoromethylalkenes. Density functional theory calculations reveal that a unique fluorine effect, arising from hyperconjugative π→σ*C‐F interactions, accounts for the regio‐reversed radical addition at the sterically hindered alkene carbon, which facilitates an unprecedented 4‐exo‐trig ring closure. This chemistry enables the direct and controllable construction of medicinally valuable quaternary‐carbon‐containing cyclobutanes from readily available raw materials, nicely complementing the existing methods. [ABSTRACT FROM AUTHOR]

Cyclobutanes are popular structural units in bioactive compounds and versatile intermediates in synthetic chemistry, but their synthesis is challenging owing to high ring strain. In this study, a novel method for highly regio‐ and diastereoselective synthesis of fluoroalkylcyclobutanes bearing vicinal quaternary and tertiary stereocenters is realized by a photocatalytic 4‐exo‐trig cyclization cascade of thioalkynes or trifluoromethylalkenes. Density functional theory calculations reveal that a unique fluorine effect, arising from hyperconjugative π→σ*C‐F interactions, accounts for the regio‐reversed radical addition at the sterically hindered alkene carbon, which facilitates an unprecedented 4‐exo‐trig ring closure. This chemistry enables the direct and controllable construction of medicinally valuable quaternary‐carbon‐containing cyclobutanes from readily available raw materials, nicely complementing the existing methods. [ABSTRACT FROM AUTHOR]

Dehydrogenation of unactivated alkanes to form versatile alkenes is an important but challenging task in synthetic chemistry. Enabled by a radical‐mediated formyl group migration, a novel visible light‐induced remote desaturation of aldehydes is developed, delivering a panel of trifluoromethylated δ,ϵ‐ or γ,δ‐unsaturated aldehydes in moderate to excellent yields with good functional group tolerance at room temperature. Mechanistic studies indicate a reaction pathway comprising the cascade trifluoromethylation of C−C double bonds, intramolecular addition to aldehydes, β‐fragmentation of alkoxy radicals, single electron transfer oxidation, and deprotonation. It provides a good complementary approach to the existing desaturation protocols. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: α‐Fluoroalkyl (Rf) alcohols are privileged motifs in drugs and pharmaceutically active compounds. As such, it is highly desirable to develop efficient methods for assembling these scaffolds. Herein, a visible‐light‐induced cascade radical cyclization of alkenyl fluoroalkyl ketones is developed, producing a variety of decorate α‐Rf cycloalkanols in promising yields with up to >20 : 1 dr selectivity. A radical chain mechanism involving an intramolecular radical addition to the α‐Rf carbonyl group and a subsequent intermolecular hydrogen atom transfer (HAT) has been proposed. Density functional theory (DFT) calculations indicate that a fluorine effect contributes to the radical addition to carbonyls by lowering the π* (C=O) orbital energy of CORf and energy barrier of the HAT between alkoxy radicals and THF, which may be valuable for controllable transformations of fluorinated molecules. [ABSTRACT FROM AUTHOR]

• A novel polymer modified electrode (PSNS-TEMPO) has been successfully prepared. • PSNS-TEMPO exhibited better electrocatalytic performance for electrooxidative self-coupling of benzylamine than PN-TEMPO. • Introduction of thiophene unit in the main chain could make the electropolymerization easier. A novel monomer 2,5-di(thienyl)pyrrole bearing TEMPO, 4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)benzoyl-oxy-2,2,6,6-tetramethylpiperidin-1-yloxy (SNS-TEMPO) was synthesized. The corresponding polymer modified electrode (PSNS-TEMPO) was successfully prepared by cyclic voltammetry, and characterized by SEM, EDS, XPS and element mapping. For comparison, another novel monomer 4-​(1H-​pyrrol-​1-​yl)​benzoyl-oxy-2,2,6,6-tetramethylpiperidin-1-yloxy (N-TEMPO) was synthesized and the corresponding polymer modified electrode (PN-TEMPO) was prepared. Introduction of thiophene unit on each side of pyrrole unit to extend the conjugation chain length was propitious to make the electropolymerization of SNS-TEMPO easier. In addition, the electrocatalytic performance for electrooxidative self-coupling of benzylamine to N -benzylidenebenzylamine on PSNS-TEMPO was better than that on PN-TEMPO prepared under similar conditions. The possible reaction mechanism of benzylamine self-oxidation coupling reaction with PSNS-TEMPO was proposed. [ABSTRACT FROM AUTHOR]

For the first time a highly selective α- and β-borylation of thioacetylenes is developed by using bis(pinacolato)diboron (II) or pinacolborane (X). [ABSTRACT FROM AUTHOR]

Difluoroalkyl groups and cyclopentenones are both important units in synthetic and medicinal chemistry. The difuoroalkylation coupled with a cyclopentenone formation still remains a challenge. Herein, we report a visible‐light‐induced cascade difluoroalkylative 5‐endo cyclization of ynones with difluoroalkyl bromides to access difluoroalkylated cyclopentenones, which may find wide applications for the concise synthesis of fluorinated cyclic molecules. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed three-component reaction between fluoroalkyl bromides, arylboronic acids, and alkenyl aldehydes has been developed and provides facile access to 5-, 6-, or 7-difluoroalkylated ketones under very mild reaction conditions. The resultant products can be smoothly converted into CF2-containing tetrahydronaphthalenes by a novel silver-catalyzed intramolecular decarboxylative cyclization of 5-aryl-2,2-difluoropentanoic acids. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed three-component reaction between fluoroalkyl bromides, arylboronic acids, and alkenyl aldehydes has been developed and provides facile access to 5-, 6-, or 7-difluoroalkylated ketones under very mild reaction conditions. The resultant products can be smoothly converted into CF2-containing tetrahydronaphthalenes by a novel silver-catalyzed intramolecular decarboxylative cyclization of 5-aryl-2,2-difluoropentanoic acids. [ABSTRACT FROM AUTHOR]

The obtained products are suitable for subsequent reactions such as Sonogashira couplings or Diels-Alder cyclizations. [ABSTRACT FROM AUTHOR]

A copper-catalyzed, redox-neutral cascade difluoroalkylation/5-endo annulation/β-fluorine cleavage of ynones is developed, providing a direct and stereoselective method to access synthetically important α-monofluoroalkenyl cyclopentanones. Mechanistic studies suggest an unprecedented CuII-assisted β-fluorine fragmentation, which may be valuable for the challenging but important C–F bond activation. Moreover, the in situ generated difluorocarbene was found to serve as an effective reductant for the regeneration of copper(I) catalyst, thus avoiding the addition of external reductants. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The first Cu‐catalyzed 1,2,5‐trifunctionalization of abundant terminal alkynes is realized by merging hydrogen atom transfer and traceless directing strategy with SR as a transient group, delivering highly functionalized aldehydes in moderate to excellent yields with broad substrate scope. The synthetic utility of this method was demonstrated by the gram‐scale reaction and downstream transformations of the resultant products. Given the high efficient installation of three different functional groups in a single reaction, it can serve as a very attractive method for rapidly assembling complex molecules from readily available starting materials. [ABSTRACT FROM AUTHOR]

In this review, we summarise the recent applications of pyridinium salts in the radical-mediated difunctionalization of alkenes. Pyridinium salts are a privileged class of compounds that show great utility in natural products and synthetic chemistry. Various organic transformations of pyridinium salts, especially in radical chemistry, have been developed in recent years. We prepared this review based on the two distinguished properties of pyridinium salts in radical transformation: (1) pyridinium salts can easily undergo single electron reduction to deliver X radicals. (2) Pyridinium salts are highly electrophilic so that alkyl radical intermediates can easily add to the pyridine core. Based on the role of pyridinium salts in difunctionalization of alkenes, the main body of this review is divided into three parts: (1) using pyridinium salts as X transfer reagents. (2) Using pyridinium salts as novel pyridine transfer reagents. (3) Using pyridinium salts as bifunctional reagents (X and pyridine). The C2 and C4 selectivity during pyridylation is discussed in detail. We hope that this review will provide a comprehensive overview of this topic and promote the wider development and application of pyridinium salts. [ABSTRACT FROM AUTHOR]

Cyclopentenes and indenes are important structural scaffolds in synthetic, medical, and material chemistry. Cyclization of alkynes via remote C−H functionalization is an appealing approach to construct these motifs due to its high efficiency and step‐economy. Herein, a traceless directing group strategy was designed to reverse the regioselectivity of radical addition which enabled an unprecedented photocatalytic sulfonylcarbocyclization of terminal alkynes by forming C−C bond on inert C(sp3)−H bond. It offers a facile access to decorated cyclopentenes and indenes under mild conditions. The resultant products could be converted into a set of valuable molecular scaffolds, including a key intermediate of AM‐6226. Mechanistic experiments suggest a radical cascade pathway comprising a Markovnikov‐type sulfonylation, 1,5‐hydrogen atom transfer, 5‐endo‐trig cyclization, and β‐elimination. This study lays further groundwork for the use of anti‐Baldwin 5‐endo‐trig radical cyclization in rapidly assembling five‐membered carbocycles. [ABSTRACT FROM AUTHOR]

Cyclopentenes and indenes are important structural scaffolds in synthetic, medical, and material chemistry. Cyclization of alkynes via remote C−H functionalization is an appealing approach to construct these motifs due to its high efficiency and step‐economy. Herein, a traceless directing group strategy was designed to reverse the regioselectivity of radical addition which enabled an unprecedented photocatalytic sulfonylcarbocyclization of terminal alkynes by forming C−C bond on inert C(sp3)−H bond. It offers a facile access to decorated cyclopentenes and indenes under mild conditions. The resultant products could be converted into a set of valuable molecular scaffolds, including a key intermediate of AM‐6226. Mechanistic experiments suggest a radical cascade pathway comprising a Markovnikov‐type sulfonylation, 1,5‐hydrogen atom transfer, 5‐endo‐trig cyclization, and β‐elimination. This study lays further groundwork for the use of anti‐Baldwin 5‐endo‐trig radical cyclization in rapidly assembling five‐membered carbocycles. [ABSTRACT FROM AUTHOR]

This report describes the site‐selective α‐functionalization of sulfonylamide derivatives through the in‐situ generation of imine intermediates. The N−F sulfonylamides, which could facilitate the elimination to generate imines, are coupled with TBACN to efficiently and mildly afford α‐amino cyanides. Comparing with Strecker reaction, this transformation offers a complementary strategy to efficiently construct α‐amino cyanides from direct α C−H functionalization of sulfonylamindes. The reaction is also characterized by broad substrate scope and flash chromatography column free workup. More importantly, the new two‐electron pathway to generate imines through manipulation of the leaving group allows us to achieve excellent α site‐selectivity. [ABSTRACT FROM AUTHOR]

A practical synthesis of 2-diarylphosphino-2′-methoxy-1,1′-binaphthalene (MOPs) was provided by employing the etherification of 1,1′-bi-2,2′-naphthol on zeolite; the ring opening of the ether with lithium; the reaction with chlorodiaryl phosphine and the resolution with (1S)-(+)-10-camphorsulfonyl chloride as the key steps. [Copyright &y& Elsevier]

[using hypervalent iodine organic compounds as oxidant]. [ABSTRACT FROM AUTHOR]

A visible-light induced three-component reaction of difluoroalkyl halides, unactivated alkenes, and alkynyl sulfones is described, providing a direct and general approach to the construction of synthetically valuable β-difluoroalkylated alkynes under room temperature conditions. This represents the first intermolecular alkynyl-difluoroalkylation of unactivated alkenes. [ABSTRACT FROM AUTHOR]

A novel photocatalytic acylarylation of unactivated alkenes using diaryliodonium salts as the arylation reagent is described. The reaction produces a variety of 2-benzyl indanones, 3,4-dihydronaphthalen-1(2H)-ones, and 2,3-dihydroquinolin-4(1H)-ones in promising yields with excellent diastereoselectivity under very mild conditions, which may be appealing for the synthesis of biologically active molecules. [ABSTRACT FROM AUTHOR]

A novel copper-catalyzed cascade difluoromethylation/cyclization of 2-(3-arylpropioloyl)benzaldehydes has been developed. This method affords an efficient and straightforward access to structurally diverse difluoromethylated naphthoquinones in one pot, starting from readily available starting materials. The reaction represents the first trans-acyldifluoromethylation of internal alkynes, which features aldehydes as acceptors for the addition of alkenyl radicals. Furthermore, this protocol can also access to monofluoromethylated naphthoquinone and difluoromethylated indanones in the same reaction condition. [ABSTRACT FROM AUTHOR]

Copper-catalyzed acyltrifluoromethylation of alkenes has been developed for the first time, affording trifluoroethyl indanones and related cyclic ketones in promising yields with excellent diastereoselectivity. The fast incorporation of CF3 and indanone into a single molecule renders it an efficient and valuable tool for the synthesis of biologically active compounds. [ABSTRACT FROM AUTHOR]

We report here a room temperature, efficient, and broadly applicable copper-catalyzed borylative cyclization of 1,n-enynyl (n = 6–9) phosphates for the concise synthesis of structurally diverse 5–8 membered cyclic 1,4-dienyl boronates, which represents the first Cu-catalyzed formal intramolecular alkyne allylboration. Subsequent Suzuki-Miyaura coupling provides a facile access to cyclized 1,4-dienes. A mechanism consisting of alkyne borylcupration, intramolecular alkene addition, and β-elimination has been proposed to explain the experimental results. [ABSTRACT FROM AUTHOR]

Copper-catalyzed cascade annulation of γ,δ-unsaturated α-bromocarbonyls with biaryl or (Z)-arylvinylacetylenes is presented, giving an expeditious access to dibenzocycloheptanes and related compounds in moderate to high yields. It provides a novel method for the one-pot synthesis of cycloheptane and cycloheptene-fused polycyclic scaffolds featuring a rare 7-endo-trig radical cyclization. [ABSTRACT FROM AUTHOR]

A regio- and stereoselective method for the synthesis of ( E)-α,β-unsaturated carbonyls has been developed v ia a silver-catalyzed tandem epoxide rearrangement/intermolecular carbonyl-heteroalkyne metathesis. Various heteroalkynes including ynol ethers, ynamides, and thioalkynes work well for this transformation, leading to the production of ( E)-α,β-unsaturated esters, amides, and thioesters in moderate to excellent yields with good functional group compatibility. It represents one of the rare examples of regio- and stereoselective intermolecular alkyne-carbonyl metathesis (ACM). [ABSTRACT FROM AUTHOR]

A straightforward, efficient, and highly diastereoselective method for the synthesis of 3,4-cyclopenta-1-tetralones has been realized via the copper-catalyzed coupling of 2-vinyl benzaldehydes with 3-alkenyl 2-bromocarbonyls. Subsequent reduction with l -selectride leads to the formation of benzannulated tricyclic alcohols, possessing four continuous stereogenic centers, in high yields with excellent diastereoselectivity. [ABSTRACT FROM AUTHOR]

A highly mono-selective ortho-trifluoromethylation of benzamides was achieved via Cu-promoted C–H activations. The reaction employs an 8-aminoquinoline group as the bidentate directing group and Togni reagent II as the CF3 source. The reaction tolerated a wide variety of functional groups and various ortho-trifluoromethylated benzamides were efficiently synthesized in 36–82% yield. [ABSTRACT FROM AUTHOR]

A Selectfluor-mediated fluorohalogenative or difluorinative hydration of ynol ethers is described, giving various α,α-fluorohalo esters including α,α-bromofluoro, α,α-chlorofluoro, α,α-fluoroiodo, and α,α-difluoro derivatives in a highly selective manner under very mild reaction conditions. The resultant products can be applied to the facile synthesis of α-monofluoro-α-amino acids. This reaction represents a new advance in the trifunctionalization of alkynes. [ABSTRACT FROM AUTHOR]

Various functionalized 2-amino-5-alkylfurans and 2-amino-5-formylfurans are selectively synthesized under mild and environmentally benign reaction conditions. [ABSTRACT FROM AUTHOR]

The presented protocol furnishes alkenyl halides with excellent regioselectivities and trans-stereoselectivities. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed trans-hydroalkynylation of N-sulfonyl ynamides has been achieved for the first time, providing α-alkynylation adducts in high yields with excellent regio- and stereoselectivity. The resulting enyne products can serve as the useful precursors for the elaboration of naphthalene derivatives via a platinum-catalyzed cycloisomerization reaction. [ABSTRACT FROM AUTHOR]

Abstract: A novel copper-catalyzed, base-free direct thiolation of xanthines and related heterocycles is described, featuring the use of inexpensive Cu(OAc)2·H2O as the catalyst, O2 as a clean and cheap oxidant, and easy-to-handle disulfides as the thiolation reagents. It works well for both aryl and alkyl disulfides. Moreover, the resultant products can be converted into 8-(hetero)aryl- or alkenyl-substituted xanthines in good yields via the Liebeskind–Srogl coupling reaction. [Copyright &y& Elsevier]

Abstract: A mild and operationally simple approach to highly functionalized oxazolones has been developed, which involves an intramolecular oxypalladation of N-alkynyl tert-butyloxycarbamates, followed by either protonolysis of the alkenyl C–Pd bond to afford 3,5-disubstituted oxazolones or allylation with allyl halides in the presence of Ag2CO3 to generate 3,4,5-trisubstituted oxazolones, respectively. [Copyright &y& Elsevier]

A Cu-catalyzed, highly regio-, and stereoselective hydroallylation of thioalkynes has been developed with allylboronates as the allylating reagents, providing stereodefined 1,4-dienyl sulfides in good to excellent yields under very mild reaction conditions. The resulting products can been smoothly converted into skipped dienes by a Ni-catalyzed coupling of C–S bonds with Grignard reagents, thus offering a novel efficient method for the regio- and stereoselective synthesis of 1,4-dienes. [ABSTRACT FROM AUTHOR]

A highly regio- and stereoselective trans -hydrofluorination of N -sulfonyl ynamides has been realized with AgF as the fluorination reagent, affording ( Z )-α-fluoroenamides in good to excellent yields. The reaction proceeds under mild reaction conditions and shows good functional group compatibility. [ABSTRACT FROM AUTHOR]

An unprecedented Pd-catalyzed trans-addition of boronic acids to ynamides has been reported, giving α,β-disubstituted enamides in high yields with excellent regio- and stereoselectivity. A possible mechanism involving the palladium carbene intermediate has been proposed to account for the unusual trans-addition. [ABSTRACT FROM AUTHOR]

Abstract: An iron-catalyzed regio- and stereoselective chlorosulfonylation of aryl chloroalkynes has been described, producing cis-1,2-dichlorovinylsulfones in satisfactory yields with good to excellent stereoselectivity (Z/E up to 95:5). A variety of functional groups such as F, NO2, Cl, Br, OMe, and t-Bu are found to be compatible under the reaction conditions. [Copyright &y& Elsevier]

A Pd-catalyzed addition of boronic acids to ynol ethers has been realized, delivering trisubstituted vinyl ethers in good yields with perfect control of the regio- and stereoselectivity. The reaction proceeds under mild conditions and exhibits excellent functional group compatibility. Moreover, the resultant products can be converted into pentasubstituted benzenes via the tandem Diels–Alder/aromatization reaction. [ABSTRACT FROM AUTHOR]

Described herein is a Pd-catalyzed haloallylation of aromatic ynol ethers and allyl chlorides, allowing facile access to (1E)-α-chloroenol ethers in a highly regio- and stereoselective manner. The synthetic utility of this method is demonstrated well by the synthesis of the stereodefined multisubstituted enol ethers and α-allylated carbonyl compounds. [ABSTRACT FROM AUTHOR]

A highly efficient and selective synthesis of (1E)- or (1Z)-1,2-dihalo-1,4-dienes viaPd-catalyzed coupling of haloalkynes and allylic halides is described. The (1E)-1,2-dihalo-1,4-dienes were generated in good yields with excellent stereoselectivities (1E/1Zup to >98/2), while (1Z)-1,2-dihalo-1,4-dienes were produced in excellent yields and stereoselectivities (1Z/1Eup to >98/2) by simply adding stoichiometric lithium halides. [ABSTRACT FROM AUTHOR]

Abstract: A palladium-catalyzed protocol for effective synthesis of 1,3-oxazolidines has been reported. This method is featured by the high diastereoselectivity (dr up to >98/2) and using the readily available 2-butene-1,4-diol derivatives and imines as substrates. [ABSTRACT FROM AUTHOR]

A novel azidative cycloisomerization of homoallenyl amides (I) and (III) using TmsN3 as the azidation reagent and a hypervalent iodine reagent as the oxidant giving a series of azidomethyl-furans (II) and (IV), resp., is presented. [ABSTRACT FROM AUTHOR]

A novel azidative cycloisomerization of homoallenyl amides (I) and (III) using TmsN3 as the azidation reagent and a hypervalent iodine reagent as the oxidant giving a series of azidomethyl-furans (II) and (IV), resp., is presented. [ABSTRACT FROM AUTHOR]

The article presents the copper-catalyzed cascade annulation of enynals with alkenyl or alkynyl α-bromocarbonyls for the synthesis of various cyclohexenone-fused polycyclic compounds.

Substrates containing aldehyde and alkene functionalities undergo trifluoromethylation and amidation under mild conditions in an one-pot manner. [ABSTRACT FROM AUTHOR]