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A unified strategy enabled the enantioselective syntheses of (−)-scholarisine G, (+)-melodinine E, (−)-leuconoxine and (−)-mersicarpine from a common 2-alkylated indole intermediate bearing an all-carbon quaternary stereogenic center. The Smith-modified Madelung indole synthesis was used to couple simple o-toluidine with chiral lactone (+)-8, incorporating the key elements for further cyclizations. Lactone (+)-8 was prepared via a palladium-catalyzed intermolecular asymmetric allylic alkylation. The unified and protecting-group-free reaction sequences allowed the synthesis of these alkaloids in a maximum of 10 steps and with high efficiency. [ABSTRACT FROM AUTHOR]

Geminal‐difluoroalkanes featuring intriguing steric and electronic properties are of great significance in medicinal chemistry, and great progresses have been achieved for their synthesis. In recent years, iodine(III) reagent‐mediated migratory gem‐difluorination of alkenes has proved to be an efficient and powerful strategy to access to diverse gem‐difluoroalkanes, especially those bearing a readily transformable functionality (TF), which are important for rapid assembly of complex gem‐difluorinated molecules in a modular and diverse manner. In this review, we systematically summarize the recent development of iodine(III)‐mediated migratory gem‐difluorination reactions for the synthesis of gem‐difluoroalkanes bearing a synthetically versatile TF at the β position. The reaction mechanism and the utilities of the products are also discussed. This review is presented and grouped basically according to the types of transformable functionalities within the products. [ABSTRACT FROM AUTHOR]

[3]DendrAl(l)ene! A new synthesis of [3]dendralenes is based on a RhIII‐catalyzed alkenyl CH activation and coupling reaction with allenyl carbinol carbonates (see scheme; DG=directing group). A variety of [3]dendralenes with diverse substitution patterns are accessible with good efficiency. The reaction is highly stereoselective and compatible with different directing groups and numerous functional groups. [ABSTRACT FROM AUTHOR]

[3]DendrAl(l)en! Eine neue [3]Dendralensynthese beruht auf einer RhIII ‐ katalysierten Alkenyl ‐ C ‐ H ‐ Aktivierung und Kupplung mit Allenylcarbinolcarbonaten (siehe Schema; DG=dirigierende Gruppe). Mit dieser Methode können zahlreiche [3]Dendralene mit verschiedenen Substitutionsmustern und hoher Stereoselektivität hergestellt werden, wobei zahlreiche dirigierende und funktionelle Gruppen toleriert werden. [ABSTRACT FROM AUTHOR]

The Rh(III)-catalyzed amidation of C(sp2)–H bonds by the use of electron-deficient aroyloxycarbamates as efficient electrophilic amidation partners is reported. The reaction proceeded under mild conditions with broad functional group tolerance, and pyridine and O-methyl hydroxamic acids serve as efficient directing groups, giving access to valuable N-Boc protected arylamines (also Fmoc and Cbz). Preliminary mechanistic experiments are discussed. [ABSTRACT FROM AUTHOR]

The synthesis of allenyl boronates is an important yet challenging topic in organic synthesis. Reported herein is an NHC‐gold‐catalyzed 1,3‐H shift toward allenyl boronates synthesis from simple propargylic B(MIDA)s. Mechanistic studies suggest dual roles of the boryl moiety in the reaction: to activate the substrate for isomerization and at the same time, to prevent the allene product from further isomerization. These effects should be a result of α‐anion stabilization and α‐cation destabilization conferred by the B(MIDA) moiety, respectively. The NHC‐Au catalyst, which is commercially available, is also found to be reactive in alkyne‐to‐1,3‐diene isomerization reactions in an atom‐economic and base‐free manner. [ABSTRACT FROM AUTHOR]

Abstract: An efficient synthesis of 4-alkyl-2(1H)-quinazolinones has been achieved by cyclization of 1-(2-alkynylphenyl)ureas (2 R2 =alkyl) in dichloroethane catalyzed by TfOH. In the case of aryl substitution (2 R2 =aryl), a mixture of quinazolinone tautomers is obtained in dichloroethane with TFA as co-solvent. Chlorination of the resulting mixture affords 4-alkyl-2-chloro-quinazolines as sole products. [Copyright &y& Elsevier]

Herein, we developed a reversible complexation mediated polymerization (RCMP) starting with a complex of iodine and organic salt as a deactivator and a thermal initiator for continuous regeneration of the organic salt activator. This novel polymerization method can be called as initiators for continuous activator regeneration (ICAR) RCMP, as inspired by the denomination of ICAR ATRP. The synthesis of poly (methyl methacrylate) (PMMA) (Mw/Mn < 1.3) with good controllability was achieved via this technique when the concentration of the deactivator complex was as low as dozens of ppm. The studied three kinds of iodine complexes showed high control on the polymerization of MMA. The effects of initiator and deactivator complex concentration on the polymerization process were researched in detail. Furthermore, the accessibility of PMMA prepared by ICAR RCMP to chain extension and block copolymerization confirmed that this novel polymerization approach afforded polymers with high chain-end fidelity. The substantial decrease in the concentration of deactivator complex or activator plays a critical role for the production and application of well-defined polymer prepared by this method. [ABSTRACT FROM AUTHOR]

The introduction of trifluoromethyl groups into organic molecules is of paramount importance in modern synthetic chemistry and medicinal chemistry. While methods for constructing C(sp2)−CF3 bonds have been well established, the advancement of practical and comprehensive approaches for forming C(sp3)−CF3 bonds remains considerably restricted. In this work, we describe an efficient and site‐specific deaminative trifluoromethylation reaction of aliphatic primary amines to afford the corresponding alkyl trifluoromethyl compounds. The reaction proceeds at room temperature with readily accessible N‐anomeric amide (Levin's reagent) and bench‐stable bpyCu(CF3)3 (Grushin's reagent, bpy=2,2′‐bipyridine) under blue light. The protocol features mild reaction conditions, good functional group tolerance, and moderate to good yields. Remarkably, the method can be applied to the direct, late‐stage trifluoromethylation of natural products and bioactive molecules. Experimental mechanistic studies were conducted, and a radical mechanism is proposed, wherein the dual roles of Grushin's reagent have been elucidated. [ABSTRACT FROM AUTHOR]

The introduction of trifluoromethyl groups into organic molecules is of paramount importance in modern synthetic chemistry and medicinal chemistry. While methods for constructing C(sp2)−CF3 bonds have been well established, the advancement of practical and comprehensive approaches for forming C(sp3)−CF3 bonds remains considerably restricted. In this work, we describe an efficient and site‐specific deaminative trifluoromethylation reaction of aliphatic primary amines to afford the corresponding alkyl trifluoromethyl compounds. The reaction proceeds at room temperature with readily accessible N‐anomeric amide (Levin's reagent) and bench‐stable bpyCu(CF3)3 (Grushin's reagent, bpy=2,2′‐bipyridine) under blue light. The protocol features mild reaction conditions, good functional group tolerance, and moderate to good yields. Remarkably, the method can be applied to the direct, late‐stage trifluoromethylation of natural products and bioactive molecules. Experimental mechanistic studies were conducted, and a radical mechanism is proposed, wherein the dual roles of Grushin's reagent have been elucidated. [ABSTRACT FROM AUTHOR]

Electrophilic addition reaction to alkynes is of fundamental importance in organic chemistry, yet the regiocontrol when reacting with unsymmetrical 1,2‐dialkyl substituted alkynes is often problematic. Herein, it is demonstrated that the rarely recognized β‐boron effect can confer a high level of site‐selectivity in several alkyne electrophilic addition reactions. A broad range of highly functionalized and complex organoborons are thus formed under simple reaction conditions starting from propargylic MIDA (N‐methyliminodiacetic acid) boronates. These products are demonstrated to be valuable building blocks in organic synthesis. In addition to the regiocontrol, this study also observes a drastic rate enhancement upon B(MIDA) substitution. Theoretical calculation reveals that the highest occupied molecular obital (HOMO) energy level of propargylic B(MIDA) is significantly raised by 0.3 eV, and the preferential electrophilic addition to the γ position is due to its higher HOMO orbital coefficient and more negative natural bond orbital (NBO) charge compared to the β position. This study demonstrates the potential of utilizing the β‐boron effect in stereoelectronic control of chemical transformations, which can inspire further research in this area. [ABSTRACT FROM AUTHOR]

Organofluorine compounds have been widely used in pharmaceutical, agrochemical, and material sciences. Reported herein are divergent fluorination reactions of vinylcyclopropanes with different electrophiles, which allow the facile synthesis of homoallylic monofluorides and vicinal‐difluorides through ring‐opening 1,5‐hydrofluorination and ring‐retaining 1,2‐difluorination, respectively. Both protocols feature mild conditions, simple operations, good functional group tolerance, and generally good yields. The practicality of these reactions is demonstrated by their scalability, as well as the successful conversion of the formed homoallylic monofluorides into other complex fluorinated molecules. [ABSTRACT FROM AUTHOR]

The facile synthesis of stereo‐defined and transformable functionality‐enriched building blocks is of great importance in modern organic chemistry, as it allows the rapid and divergent assembly of complex molecules. Herein a halogen electrophile (N‐bromosuccinimide and N‐iodosuccinimide) initiated semipinacol rearrangement reaction of B(MIDA)‐propargylic alcohols (MIDA=N‐methyliminodiacetyl) by aryl migration towards the synthesis of amphoteric α‐haloalkenyl boronates in moderate to good yields with excellent stereoselectivities is reported. The value of the products is evidenced by their ability to undergo divergent conversions to polysubstituted alkenes through manipulation of the C−B and C−X (X=Br, I) bonds and the carbonyl group. [ABSTRACT FROM AUTHOR]

This method gives access to a variety of [3]dendralenes with diverse substitution patterns and diene-substituted arenes. [ABSTRACT FROM AUTHOR]

The presented reaction proceeds under mild conditions with a broad functional group tolerance. [ABSTRACT FROM AUTHOR]

Allylic carbonates are useful reagents for the ortho-directed allylation of a variety of aromatic carboxylic N,N-diisopropylamides in the presence of a Rh/Ag-mixed catalyst. [ABSTRACT FROM AUTHOR]

The synthesized boron-substituted heterocycles are useful for further transformations, e. [ABSTRACT FROM AUTHOR]

The novel oxidative coupling reaction of N-pivaloyloxybenzamides or heterocyclic analogues with allenes affords a variety of dihydroisoquinoline derivatives. [ABSTRACT FROM AUTHOR]

The direct trifluoromethylthiolation of arenes was realized via (pentamethylcyclopentadienyl)cobalt(III)-catalyzed C(sp2)-H activation and coupling with AgSCF3 under the assistance of a directing group. The reaction features redox-neutrality, mild conditions, broad substrate scope, and good functional group tolerance. Preliminary mechanistic studies have been conducted. [ABSTRACT FROM AUTHOR]

In this paper, gradient and block polycarboxylate ether superplasticizers (PCEs) composed of allyl alcohol polyoxyethylene ether macromonomer and acrylic acid were synthesized via aqueous reversible addition-fragmentation chain transfer (RAFT) polymerization. The molecular structure of PCEs was characterized by 1H nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR) spectroscopy, and size exclusion chromatography (SEC), and the fluidity of cement paste and the influence of SO42− on the dispersibility of PCEs were investigated in detail. The experimental results show that the molecular weight and polydispersity of the obtained PCEs were well controlled by the RAFT process. Compared with the PCEs prepared by conventional free radical polymerization, the gradient PCEs synthesized by RAFT polymerization exhibited excellent dispersion capability. The range of molecular weights and acid-ether ratios of the gradient PCEs for high fluidity of cement paste was much wider. Furthermore, PCEs with gradient structure also showed excellent sulfate resistance. In contrast, PCEs with block architecture exhibited the lowest flowability. Based on these findings, the relationship between dispersibility of PCEs and their chemical structures was illustrated. [ABSTRACT FROM AUTHOR]

A mild, selective and redox-neutral Cp*Ir(III)- and Cp*Rh(III)-catalyzed C–H activation/annulation of salicylaldehydes with fluorovinyl tosylates is reported. The use of monofluorovinyl tosylate favors the synthesis of C2- and C3-substitution-free chromones via C–H activation/β-F elimination/annulation, whereas difluorovinyl tosylate leads to the construction of C2-fluoroalkoxy chromones. Mild reaction conditions and good functional-group tolerance were observed. Further functionalization of the resulting chromones via halogenation, alkynylation, alkylation and hydrocyanation was successfully realized. [ABSTRACT FROM AUTHOR]

Abstract: A highly efficient one-pot synthesis of 2-chloro-3-substituted quinolines has been developed by tetrabutylammonium chloride-triggered 6-endo cyclization of o-alkynylisocyanobenzenes, which are generated in situ by dehydration of the corresponding N-(2-ethynylphenyl)formamides. [Copyright &y& Elsevier]

α‐Haloboronates are useful organic synthons that can be converted to a diverse array of α‐substituted alkyl borons. Methods to α‐haloboronates are limiting and often suffer from harsh reaction conditions. Reported herein is a photochemical radical C‐H halogenation of benzyl N‐methyliminodiacetyl (MIDA) boronates. Fluorination, chlorination, and bromination reactions were effective by using this protocol. Upon reaction with different nucleophiles, the C−Br bond in the brominated product could be readily transformed to a series of C−C, C−O, C−N, C−S, C−P, and C−I bonds, some of which are difficult to forge with α‐halo sp2‐B boronate esters. An activation effect of B(MIDA) moiety was found. [ABSTRACT FROM AUTHOR]

α‐Haloboronates are useful organic synthons that can be converted to a diverse array of α‐substituted alkyl borons. Methods to α‐haloboronates are limiting and often suffer from harsh reaction conditions. Reported herein is a photochemical radical C‐H halogenation of benzyl N‐methyliminodiacetyl (MIDA) boronates. Fluorination, chlorination, and bromination reactions were effective by using this protocol. Upon reaction with different nucleophiles, the C−Br bond in the brominated product could be readily transformed to a series of C−C, C−O, C−N, C−S, C−P, and C−I bonds, some of which are difficult to forge with α‐halo sp2‐B boronate esters. An activation effect of B(MIDA) moiety was found. [ABSTRACT FROM AUTHOR]

The synthesis of α-boryl halohydrins via difunctionalization of alkenyl MIDA boronates has been reported. Intriguing stereoselectivity was found with different halogen sources, which arises from the special stabilizing effect of the B(MIDA) moiety. The transformation provided cis addition products using Cl+ or Br+ as the halogen source, while trans addition products were obtained when I+ was employed. [ABSTRACT FROM AUTHOR]

The iodofluorination of alkynyl and alkenyl MIDA (N-methyliminodiacetyl) boronates led to the synthesis of two types of fluorinated organoborons bearing a valuable C–I bond. The B(MIDA) moiety confers exclusive regioselectivity to the reaction, and the products were formed in generally good yields. Preliminary utility of the products was demonstrated. [ABSTRACT FROM AUTHOR]

The ring‐opening reactions of N‐methyliminodiacetyl (MIDA) α‐chloroepoxyboronates with different nucleophiles allow the modular synthesis of a diverse array of organoboronates. These include seven types of α‐functionalized acylboronates and seven types of borylated heteroarenes, some of which are difficult‐to‐access products using alternative methods. The common synthons, α‐chloroepoxyboronates, could be viably synthesized by a two‐step procedure from the corresponding alkenyl MIDA boronates. Mild reaction conditions, good functional‐group tolerance, and generally good efficiency were observed. The utility of the products was also demonstrated. [ABSTRACT FROM AUTHOR]

The ring‐opening reactions of N‐methyliminodiacetyl (MIDA) α‐chloroepoxyboronates with different nucleophiles allow the modular synthesis of a diverse array of organoboronates. These include seven types of α‐functionalized acylboronates and seven types of borylated heteroarenes, some of which are difficult‐to‐access products using alternative methods. The common synthons, α‐chloroepoxyboronates, could be viably synthesized by a two‐step procedure from the corresponding alkenyl MIDA boronates. Mild reaction conditions, good functional‐group tolerance, and generally good efficiency were observed. The utility of the products was also demonstrated. [ABSTRACT FROM AUTHOR]

An efficient synthesis of highly functionalized cyclohexadienylborons via an inverse electron‐demand Diels–Alder reaction/CO2 extrusion of alkenyl MIDA boronates with 2‐pyrones is outlined. By controlling the reaction temperature, the corresponding C(sp3)‐rich bicyclolactones could also be readily formed. The exo‐selective reactions feature good functional‐group tolerance, broad substrate scope, and excellent regio‐ and diastereoselectivity. Oxidation of the cyclohexadienylborons in a one‐pot procedure led to the construction of aromatic boronates bearing valuable functional groups. Synthetic transformations of the C−B bond were demonstrated. Boron: An efficient synthesis of highly functionalized cyclohexadienylborons by an inverse‐electron‐demand Diels–Alder reaction/CO2 extrusion of alkenyl MIDA boronates with 2‐pyrones is outlined (see scheme). [ABSTRACT FROM AUTHOR]

Organofluorine compounds are widely used in pharmaceutical, agrochemical, and materials sciences. The syntheses and applications of fluorinated organoborons facilitate the rapid and modular assemblies of fluorine‐containing molecules because of the versatility of C−B bonds in diverse chemical transformations. Reported herein is a migratory geminal difluorination of aryl‐substituted alkenyl N‐methyliminodiacetyl (MIDA) boronates using commercially available Py⋅HF as the fluorine source and hyperiodine as the oxidant. The protocol offers facile access to α‐ and β‐difluorinated alkylboron compounds, both of which have previously been challenging to prepare. Mild reaction conditions, broad substrate scope, good functional‐group tolerance, and moderate to good yields were observed. The utility of these products is demonstrated by further transformations of the C−B bond into other valuable functional groups. On the move: A migratory geminal difluorination of aryl‐substituted alkenyl N‐methyliminodiacetyl (MIDA) boronates using commercially available Py⋅HF as the fluorine source is reported. The protocol offers an unprecedented opportunity for the synthesis of α‐ and β‐difluorinated alkylboron compounds. Mild reaction conditions, broad substrate scope, good functional‐group tolerance, and moderate to good yields were observed. [ABSTRACT FROM AUTHOR]

Organofluorine compounds are widely used in pharmaceutical, agrochemical, and materials sciences. The syntheses and applications of fluorinated organoborons facilitate the rapid and modular assemblies of fluorine‐containing molecules because of the versatility of C−B bonds in diverse chemical transformations. Reported herein is a migratory geminal difluorination of aryl‐substituted alkenyl N‐methyliminodiacetyl (MIDA) boronates using commercially available Py⋅HF as the fluorine source and hyperiodine as the oxidant. The protocol offers facile access to α‐ and β‐difluorinated alkylboron compounds, both of which have previously been challenging to prepare. Mild reaction conditions, broad substrate scope, good functional‐group tolerance, and moderate to good yields were observed. The utility of these products is demonstrated by further transformations of the C−B bond into other valuable functional groups. [ABSTRACT FROM AUTHOR]

A Cp*Co(iii)-catalyzed [5+2] C–H annulation reaction of 2-vinylphenols with ynamides was developed. The reaction led to the efficient synthesis of valuable 2-aminobenzoxepines in high regioselectivity. Mild reaction conditions, good functional group tolerance, and moderate to good yields were observed. The synthetic utility was demonstrated by a gram-scale synthesis and further transformations of the products. Preliminary mechanistic studies were conducted, and a possible catalytic cycle was proposed. [ABSTRACT FROM AUTHOR]

Abstract: A cobalt‐catalyzed decarboxylative Negishi coupling reaction of redox‐active aliphatic esters with organozinc reagents was developed. The method enabled efficient alkyl–aryl, alkyl–alkenyl, and alkyl–alkynyl coupling reactions under mild reaction conditions with no external ligand or additive needed. The success of an in situ activation protocol and the facile synthesis of the drug molecule (±)‐preclamol highlight the synthetic potential of this method. Mechanistic studies indicated that a radical mechanism is involved. [ABSTRACT FROM AUTHOR]

Abstract: A cobalt‐catalyzed decarboxylative Negishi coupling reaction of redox‐active aliphatic esters with organozinc reagents was developed. The method enabled efficient alkyl–aryl, alkyl–alkenyl, and alkyl–alkynyl coupling reactions under mild reaction conditions with no external ligand or additive needed. The success of an in situ activation protocol and the facile synthesis of the drug molecule (±)‐preclamol highlight the synthetic potential of this method. Mechanistic studies indicated that a radical mechanism is involved. [ABSTRACT FROM AUTHOR]

A novel synthesis of α-CF3 and α-CF2H amines via the aminofluorination of gem-difluoroalkenes and mono-fluoroalkenes, respectively, is reported. The method employs Selectfluor as an electrophilic fluorine source and acetonitrile as a nitrogen source. Mechanistic studies revealed a single-electron oxidation/fluorine-abstraction/Ritter-type amination pathway. The protocol allowed the synthesis of a broad range of fluorinated amines including those bearing quaternary carbon centers with good efficiency and functional group tolerance. [ABSTRACT FROM AUTHOR]

Abstract: The copper‐catalyzed stereoselective defluorinative borylation and silylation of gem‐difluoroalkenes was developed. The protocol led to the exclusive formation of Z type monofluoroalkenyl borons and silanes in generally good efficiency with broad substrate scope. The products formed could be readily transformed to other F‐containing molecules by taking advantage of the versatile reactivities of C−B and C−Si bonds. Experimental and theoretical mechanistic studies were conducted which support an olefin insertion/syn‐planar β‐F elimination pathway. [ABSTRACT FROM AUTHOR]

The individual molecules of α-chloroalkenyl boronates include both an electrophilic C−Cl bond and a nucleophilic C−B bond, which makes them intriguing organic synthons. Reported herein is a stereodivergent synthesis of both E and Z α-chloroalkenyl N-methyliminodiacetyl (MIDA) boronates through the direct chlorination of alkenyl MIDA boronates using tBuOCl and PhSeCl reagents, respectively. Both reaction processes are stereospecific and the use of sp3-B MIDA boronate is the key contributor to the reactivity. The synthetic value of the boronate products was also demonstrated. [ABSTRACT FROM AUTHOR]

The individual molecules of α-chloroalkenyl boronates include both an electrophilic C−Cl bond and a nucleophilic C−B bond, which makes them intriguing organic synthons. Reported herein is a stereodivergent synthesis of both E and Z α-chloroalkenyl N-methyliminodiacetyl (MIDA) boronates through the direct chlorination of alkenyl MIDA boronates using tBuOCl and PhSeCl reagents, respectively. Both reaction processes are stereospecific and the use of sp3-B MIDA boronate is the key contributor to the reactivity. The synthetic value of the boronate products was also demonstrated. [ABSTRACT FROM AUTHOR]

Heteroarenes are important structural motif in functional molecules. A MnI-catalyzed 1,2-diheteroarylation of allenes via a C−H activation/Smiles rearrangement cascade is presented. The reaction occurred under additive-free or even solvent-free conditions, which allowed the creation of two C−C and one C−N bonds in a single operation. A series of structurally diverse bicyclic or tricyclic compounds bearing an exocyclic double bond were constructed in good to excellent efficiency. The decarboxylative ring-opening of the products led to the facile synthesis of vicinal biheteroaryls. Synthetic applications were demonstrated and preliminary mechanistic studies were conducted. [ABSTRACT FROM AUTHOR]

A redox-neutral bimetallic Rh(iii)/Ag(i) relay catalysis allowed the efficient construction of 3-alkylidene isoindolinones and 3-alkylidene isobenzofuranones. The Rh(iii) catalyst was responsible for the C–H monofluoroalkenylation reaction, whereas the Ag(i) salt was an activator for the follow-up cyclization. The methodology developed was applied as a key step in the rapid total synthesis of the natural product aristolactam BII. [ABSTRACT FROM AUTHOR]

Fluorinated heterocycles play an important role in pharmaceutical and agrochemical industries. Herein, we report on the synthesis of four types of fluorinated heterocycles via rhodium(III)-catalyzed C?H activation of arenes/alkenes and versatile coupling with 2,2-difluorovinyl tosylate. With N-OMe benzamide being a directing group (DG), the reaction delivered a monofluorinated alkene with the retention of the tosylate functionality. Subsequent one-pot acid treatment allowed the efficient synthesis of 4-fluoroisoquinolin-1(2H)-ones and 5-fluoropyridin-2(1H)-ones. When N?OPiv benzamides were used, however, [4 + 2] cyclization occurred to provide gem-difluorinated dihydroisoquinolin-1(2H)-ones. Synthetic applications have been demonstrated and the ready availability of both the arene and the coupling partner highlighted the synthetic potentials of these protocols. Mechanistically, these two processes share a common process involving N?H deprotonation, C?H activation, and olefin insertion to form a 7-membered rhodacycle. Thereafter, different reaction pathways featuring β-F elimination and C?N bond formation are followed on the basis of density functional theory (DFT) studies. These two pathways are DG-dependent and led to the open chain and cyclization products, respectively. The mechanistic rationale was supported by detailed DFT studies. In particular, the origins of the intriguing selectivity in the competing β-F elimination versus C?N bond formation were elucidated. It was found that β-F elimination is a facile event and proceeds via a syn-coplanar transition state with a low energy barrier. The C?N bond formation proceeds via a facile migratory insertion of the Rh?C(alkyl) into the Rh(V) amido species. In both reactions, the migratory insertion of the alkene is turnover-limiting, which stays in good agreement with the experimental studies. [ABSTRACT FROM AUTHOR]

Abstract: The prenyl group is an important component in bioactive compounds. Herein, we report the assembly of prenylated heteroarenes through a cascade Minisci reaction and acid‐promoted dehydration sequence. The use of potassium (3‐hydroxy‐3‐methylbut‐1‐yl)trifluoroborate as a new coupling reagent allows the direct introduction of prenyl and 3‐hydroxy‐3‐methylbutyl groups to a wide variety of electron‐deficient heteroarenes. Synthetic application is also demonstrated. [ABSTRACT FROM AUTHOR]

The synthesis of halogenated and trifluoromethylated α-boryl ketones via a one-pot oxidative difunctionalization of alkenyl MIDA boronates is reported. These novel densely functionalized organoborons bearing synthetically and functionally valuable carbonyl, halogen/CF3 and boronate moieties within the same molecule are synthetically challenging for the chemist, but have great synthetic potential, as demonstrated by their applications in a straightforward synthesis of borylated furans. The generality of this reaction was extensively investigated. This reaction is attractive since the starting materials, alkenyl MIDA boronates, are easily accessible. [ABSTRACT FROM AUTHOR]

The synthesis of halogenated and trifluoromethylated α-boryl ketones via a one-pot oxidative difunctionalization of alkenyl MIDA boronates is reported. These novel densely functionalized organoborons bearing synthetically and functionally valuable carbonyl, halogen/CF3 and boronate moieties within the same molecule are synthetically challenging for the chemist, but have great synthetic potential, as demonstrated by their applications in a straightforward synthesis of borylated furans. The generality of this reaction was extensively investigated. This reaction is attractive since the starting materials, alkenyl MIDA boronates, are easily accessible. [ABSTRACT FROM AUTHOR]