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The reducing power of iodide anion is an underexplored property that can be used for the cross-electrophile coupling of organic molecules. Herein we harness this trait for the preparation of tertiary amines through the combination of two simple reagents: an electrophilic-carbon precursor and an iminium iodide in a dual role - both as nitrogen-containing building block and as reducing agent. The underlying mechanism of this new C-C bond-formation paradigm is explored through a combination of experiment and quantum chemical calculations., (© 2024 The Author(s). Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

C-H functionalization of purely aliphatic substrates is a challenging endeavor, as the absence of directing groups generally thwarts attempts at regiocontrol. This is particularly true for difunctionalization reactions, where the control of relative stereochemistry poses an additional obstacle. The Baddeley reaction of decalins, despite suffering from strong limitations with regard to yield and generality, stands as one of only few known transformations capable of regio- and stereocontrol in aliphatic C-H functionalization. Herein, we report a regio- and diastereoselective method for the double functionalization of decalins enabling access to a novel, unreported regioisomer in synthetically useful yields. This method was also successfully applied to a range of other alkane substrates, enabling a straightforward synthesis of keto alcohols from the simplest alkane building blocks., (© 2024 The Author(s). Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

An enantioconvergent palladium-catalyzed Negishi cross-coupling with racemic secondary organozinc reagents has been developed, enabling access to enantioenriched 1,1-diarylalkane motifs in high yields and enantioselectivities. Computational data indicates that the racemization of organozinc compounds most likely occurs through a bridged bimolecular mechanism., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The synthesis of enantioenriched α-substituted 1,3-dicarbonyls remains a contemporary challenge in synthesis due to their tendency to undergo racemization via keto-enol tautomerization. Herein, we report a method to access enantioenriched β-ketoamides by a chiral sulfinimine-mediated [3,3]-sigmatropic sulfonium rearrangement. The transformation displays good chirality transfer, as well as excellent chemoselectivity and functional group tolerance. Diastereoselective reduction of the ketone moiety, also achievable in one-pot fashion, affords enantioenriched β-hydroxyamides., (© 2024 The Author(s). Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Inverse hydride shuttle catalysis provides a multicomponent platform for the highly efficient synthesis of alkaloid frameworks with exquisite diastereoselectivity. However, a number of limitations hinder this method, primarily the strict requirement for highly electron-deficient acceptors. Herein, we present a general Lewis acid-driven approach to address this constraint, and have developed two broad strategies enabling the modular synthesis of complex azabicycles that were entirely unattainable using the previous method. The enhanced synthetic flexibility facilitates a streamlined asymmetric cyclization, leading to a concise total synthesis of the alkaloid (-)-tashiromine., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The deployment of small-molecule fluorescent agents plays an ever-growing role in medicine and drug development. Herein, we complement the portfolio of powerful fluorophores, reporting the serendipitous discovery and development of a novel class with an imidazo[1,2-a]pyridinium triflate core, which we term PyrAtes. These fluorophores are synthesized in a single step from readily available materials (>60 examples) and display Stokes shifts as large as 240 nm, while also reaching NIR-I emissions at λ max as long as 720 nm. Computational studies allow the development of a platform for the prediction of λ max and λ Em . Furthermore, we demonstrate the compatibility of these novel fluorophores with live cell imaging in HEK293 cells, suggesting PyrAtes as potent intracellular markers., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The nature of protecting group chemistry necessitates a deprotection step to restore the initially blocked functionality prior to further transformation. As this aspect of protecting group manipulation inevitably adds to the step count of any synthetic sequence, the development of methods enabling simultaneous deprotection and functionalization ("deprotective functionalization"-distinct from "deprotection followed by functionalization") is appealing, as it has the potential to improve efficiency and streamline synthetic routes. Herein, we report a deprotective functionalization of the newly introduced Nms-amides guided by density functional theory (DFT) analysis, which exploits the inherent Nms reactivity. Mechanistic studies further substantiate and help rationalize the exquisite reactivity of Nms-amides, as other commonly used protecting groups are shown not to exhibit the same reactivity patterns. The practicality of this approach was ultimately demonstrated in selected case studies., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Sulfenyl imidinium salts are a virtually unexplored class of intermediates in organic chemistry. Herein, we demonstrate how sulfonium rearrangements can be deployed to access these versatile synthetic intermediates, bearing three contiguous (and congested) stereogenic centers, with high levels of selectivity. The synthetic value of the scaffold was unraveled by selective transformations into a range of building blocks, including 1,4-dicarbonyl derivatives and sulfonolactones., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The combination of Lewis bases with α,β-unsaturated carbonyls allows the in-situ generation of enolates without the need for strong Brønsted bases. Recently developed synthetic methods employ this approach for arylation followed by elimination of the Lewis base, regenerating the alkene. This strategy has been deployed for formal α- or β-C-H arylation in different contexts, namely (a) transition metal catalysis, (b) rearrangement reactions utilizing hypervalent main group elements and (c) organocatalysis. This concept article provides an overview of the developed strategies, highlighting and contextualizing their features., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

p-Toluenesulfonyl (Tosyl) and nitrobenzenesulfonyl (Nosyl) are two of the most common sulfonyl protecting groups for amines in contemporary organic synthesis. While p-toluenesulfonamides are known for their high stability/robustness, their use in multistep synthesis is plagued by difficult removal. Nitrobenzenesulfonamides, on the other hand, are easily cleaved but display limited stability to various reaction conditions. In an effort to resolve this predicament, we herein present a new sulfonamide protecting group, which we term Nms. Initially developed through in silico studies, Nms-amides overcome these previous limitations and leave no room for compromise. We have investigated the incorporation, robustness and cleavability of this group and found it to be superior to traditional sulfonamide protecting groups in a broad range of case studies., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

We report herein a straightforward transfer of a free amino group (NH 2 ) from a commercially available nitrogen source to unfunctionalized, native carbonyls (amides and ketones) resulting in direct α-amination. Primary α-amino carbonyls are readily produced under mild conditions, further enabling diverse in situ functionalization reactions-including peptide coupling and Pictet-Spengler cyclization-that capitalize on the presence of the unprotected primary amine., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The demand for new biomass-derived fine and commodity chemicals propels the discovery of new methodologies and synthons. Whereas furfural and 5-hydroxymethylfurfural are cornerstones of sustainable chemistry, 3-acetamido-5-acetyl furan (3A5AF), an N-rich furan obtained from chitin biomass, remains unexplored, due to the poor reactivity of the acetyl group relative to previous furanic aldehydes. Here we developed a reactive 3-acetamido-5-furfuryl aldehyde (3A5F) and demonstrated the utility of this synthon as a source of bio-derived nitrogen-rich heteroaromatics, carbocycles, and as a bioconjugation reagent., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

α-Amino acid derivatives are key components of the molecules of life. The synthesis of α-amino carbonyl/carboxyl compounds is a contemporary challenge in organic synthesis. Herein, we report a practical method for the preparation of α-amino acid derivatives via direct hydrative amination of activated alkynes under mild conditions, relying on sulfinamides as the nitrogen source. Computational studies suggest that the reaction is enabled by a new type of sulfonium [2,3]-sigmatropic rearrangement., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

In contrast to ketones and carboxylic esters, amides are classically seen as comparatively unreactive members of the carbonyl family, owing to their unique structural and electronic features. However, recent decades have seen the emergence of research programmes focused on the selective activation of amides under mild conditions. In the past four years, this area has continued to rapidly develop, with new advances coming in at a fast pace. Several novel activation strategies have been demonstrated as effective tools for selective amide activation, enabling transformations that are at once synthetically useful and mechanistically intriguing. This Minireview comprises recent advances in the field, highlighting new trends and breakthroughs in what could be called a new age of amide activation., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Herein we report a method for the synthesis of α-aryl acrylamides leveraging polar S-to-C aryl migrations induced by a Lewis basic organocatalyst. In contrast to previously reported radical aryl migrations of sulfonyl acrylimides, this polar process enables subsequent elimination, ultimately leading to a formal aryl/hydrogen exchange including SO 2 extrusion. This reaction is selective for electron-deficient aromatic groups, while tolerating a variety of substituents on nitrogen and in the β-position, and it delivers useful building blocks for further transformations, including cycloaddition and cyclisation reactions. The mechanism was investigated in detail using quantum chemical calculations, which unexpectedly revealed the Lewis base to be involved in several decisive steps., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The development of reactions converting alkenes and alkynes into valuable building blocks remains one of the main goals of synthetic chemistry. Herein, we present the leveraging of highly electron-deficient iminium ions, rare and fleeting intermediates, into a general amine synthesis. This enables the preparation of amines bearing e.g. valuable α-trifluoromethyl moieties under mild conditions. This broad concept is highlighted by the late-stage amination of quinine into a biologically interesting new analogue., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

A direct C-C coupling process that merges Michael acceptors and Eschenmoser's salt is presented. Although reminiscent of the Morita-Baylis-Hillman reaction, this process requires no Lewis base catalyst. The underlying mechanism was unveiled by a combination of kinetic, isotopic labelling experiments as well as computational investigations, which showcased the critical role of HFIP as a superior mediator for proton-transfer events as well as the decisive role of the halide counterion., (© 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

A chemoselective and robust protocol for the γ-oxidation of β,γ-unsaturated amides is reported. In this method, electrophilic amide activation, in a rare application to unsaturated amides, enables a regioselective reaction with TEMPO resulting in the title products. Radical cyclisation reactions and oxidation of the synthesised products highlight the synthetic utility of the products obtained., (© 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

A selenium-catalysed para-hydroxylation of N-aryl-hydroxamic acids is reported. Mechanistically, the reaction comprises an N-O bond cleavage and consecutive selenium-induced [2,3]-rearrangement to deliver para-hydroxyaniline derivatives. The mechanism is studied through both 18 O-crossover experiments as well as quantum chemical calculations. This redox-neutral transformation provides an unconventional synthetic approach to para-aminophenols., (© 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

A synthetically convenient approach for the direct α-deuteration of amides is reported. This mechanistically unusual process relies on a retro-ene-type process, triggered by the addition of deuterated dimethyl sulfoxide to a keteniminium intermediate, generated through electrophilic amide activation. The transformation displays broad functional-group tolerance and high deuterium incorporation., (© 2020 The Authors. Published by Wiley-VCH GmbH.)

Triflic anhydride mediated activation of acetophenones leads to highly electrophilic intermediates that can undergo a variety of transformations when treated with nucleophiles. This electrophilic ketone activation gives access to α-arylated and α-oxyaminated acetophenones under metal-free conditions in moderate to excellent yields and enables extension to the synthesis of arylated morpholines via generation of vinylsulfonium salts. Computational investigations confirmed the transient existence of intermediates derived from vinyl triflates and the role of the oxygen atoms at the para position of aromatic ring in facilitating their stabilisation., (© 2020 The Authors. Published by Wiley-VCH GmbH.)

The reactivity of iodine(III) reagents towards nucleophiles is often associated with umpolung and cationic mechanisms. Herein, we report a general process converting a range of ketone derivatives into α-cyclopropanated ketones by oxidative umpolung. Mechanistic investigation and careful characterization of side products revealed that the reaction follows an unexpected pathway and suggests the intermediacy of non-classical carbocations., (© 2020 The Authors. Published by Wiley-VCH GmbH.)

The metal-promoted nucleophilic addition of sulfur ylides to π-systems is a well-established reactivity. However, the driving force of such transformations, elimination of a sulfide moiety, entails stoichiometric byproducts making them unfavorable in terms of atom economy. In this work, a new take on sulfur ylide chemistry is reported, an atom-economical gold(I)-catalyzed synthesis of dihydrobenzo[b]thiepines. The reaction proceeds under mild conditions at room temperature., (© 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

The work presented herein describes the synthesis of a formerly inaccessible class of heterocyclic compounds. The reaction relies on α-phthalimido-amides, which are readily prepared from amino acids in 2 simple reactions steps. Under amide activation conditions in which classical keteniminium ions are not formed, the nitrile solvent is incorporated into the new fused 7-membered ring system. Due to the absence of a keteniminium intermediate, the stereogenic information in the α-position is fully retained., (© 2020 The Authors. Published by Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim.)

The ability of silicon to stabilize vinyl cationic species leads to a redox arylation of alkynes whereby the stringent limitations of reactivity and regioselectivity of alkyl-substituted alkynes are lifted. This allows the synthesis of a range of α-silyl-α'-arylketones under mild conditions in good to excellent yields and with high functional group tolerance, whereby the silicon moiety in the final products can either be removed for a formal acetone monoarylation transform, or capitalized upon for subsequent electrophilic substitutions at either side of the carbonyl group., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

In comparison to the extensively studied metal-catalyzed hydroamination reaction, hydroaminomethylation has received significantly less attention despite its considerable potential to streamline amine synthesis. State-of-the-art protocols for hydroaminomethylation of alkenes rely largely on transition-metal catalysis, enabling this transformation only under highly designed and controlled conditions. Here we report a broadly applicable, acid-mediated approach to the hydroaminomethylation of unactivated alkenes and alkynes. This methodology employs cheap, readily available, and bench-stable reactants and affords the desired amines with excellent functional group tolerance and impeccable regioselectivity. The broad scope of this transformation, as well as mechanistic investigations and in situ domino functionalization reactions are reported., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

A regio- and chemoselective preparation of bicyclic alkoxyoxazolium salts from amide derivatives of proline and pipecolic acid by electrophilic amide activation is reported. Mechanistic NMR experiments suggest an unusual role for the base and highlight the effect of substitution pattern of the substrates., (© 2019 The Authors. Published by Wiley‐VCH Verlag GmbH & Co. KGaA.)

A synthetically useful approach for the direct α-arylation of carbonyl compounds through a novel oxidative C-C bond activation is reported. This mechanistically unusual process relies on a 1,2-aryl shift and results in all-carbon quaternary centers. The transformation displays broad functional-group tolerance and can in principle also be applied as an asymmetric variant., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

A flexible redox-neutral coupling of aldehydes and alkenes enables rapid access to stereotriads starting from a single stereocenter with perfect levels of enantio- and diastereoselectivity under mild conditions. The versatility of the method is highlighted by the installation of heteroatoms along the tether, which enables a route to structurally diverse building blocks. The formal synthesis of (+)-neopeltolide further demonstrates the synthetic utility of this approach., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

A computational study of the electrocyclic ring-opening of 2-substituted cyclobutenecarboxylic acids is presented. Detailed calculations suggest a model to predict whether the product of nucleophilic alkylation of a bicyclic lactone electrophile will be a cyclobutenecarboxylic acid or its dienoic acid isomer, based on the used nucleophile.

We report a method for the selective α,β-dehydrogenation of amides in the presence of other carbonyl moieties under mild conditions. Our strategy relies on electrophilic activation coupled to in situ selective selenium-mediated dehydrogenation. The α,β-unsaturated products were obtained in moderate to excellent yields, and their synthetic versatility was demonstrated by a range of transformations. Mechanistic experiments suggest formation of an electrophilic Se IV species., (© 2018 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

A ruthenium-catalysed cross-olefination of diazo compounds and sulfoxonium ylides is presented. Our reaction design exploits the intrinsic difference in reactivity of diazo compounds and sulfoxonium ylides as both carbene precursors and nucleophiles, which results in a highly selective reaction., (© 2018 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

A concise and efficient total synthesis of the lignan natural product larreatricin as well as an unambiguous assignment of configuration of its enantiomers are reported, resolving a long-held controversy. Enzyme kinetic studies revealed that different polyphenol oxidases show high and remarkably divergent enantioselective recognition of this secondary metabolite., (© 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Phosphonates have garnered considerable attention for years owing to both their singular biological properties and their synthetic potential. State-of-the-art methods for the preparation of mixed phosphonates, phosphonamidates, phosphonothioates, and phosphinates rely on harsh and poorly selective reaction conditions. We report herein a mild method for the modular preparation of phosphonylated derivatives, several of which exhibit interesting biological activities, that is based on chemoselective activation with triflic anhydride. This procedure enables flexible and even iterative substitution with a broad range of O, S, N, and C nucleophiles., (© 2018 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

We report a novel approach to the classical natural product quinine that is based on two stereoselective key steps, namely a C-H activation and an aldol reaction, to unite the two heterocyclic moieties of the target molecule. This straightforward and flexible strategy enables a concise synthesis of natural (-)-quinine, the first synthesis of unnatural (+)-quinine, and also provides access to unprecedented C3-aryl analogues, which were prepared in only six steps. We additionally demonstrate that these structural analogues exhibit improved antimalarial activity compared with (-)-quinine both in vitro and in mice infected with Plasmodium berghei., (© 2018 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Machines learn chemistry: An artificial intelligence algorithm has learned to predict the outcomes of C-N coupling reactions from a few thousand nanomole-scale experiments. This Highlight discusses this work in the context of other state-of-the-art approaches for predicting the yields of organic reactions and explains the significance of the results., (© 2018 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Organic synthesis boasts a wide array of reactions involving either radical species or ionic intermediates. The combination of radical and polar species, however, has not been explored to a comparable extent. Herein we present the hydrative aminoxylation of ynamides, a reaction which can proceed by either a polar-radical crossover mechanism or through a rare cationic activation. Common to both processes is the versatility of the persistent radical TEMPO and its oxidised oxoammonium derivative TEMPO + . The unique mechanisms of these processes are elucidated experimentally and by in-depth DFT-calculations., (© 2018 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

A novel ynamide preactivation strategy enables the use of otherwise incompatible reagents and allows preparation of α,β-disubstituted enamides with high regio- and stereoselectivity. Mechanistic analysis reveals the intermediacy of a triflate-bound intermediate as a solution-stable, effective keteniminium reservoir, whilst still allowing subsequent addition of organometallic reagents., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The lupin alkaloid sparteine is a well-known chiral diamine with a range of applications in asymmetric synthesis, as well as a blocker of voltage-gated sodium channels (VGSCs). However, there is only scarce information on the VGSC-blocking activity of sparteine derivatives where the structure of the parent alkaloid is retained. Building on the recent renewed availability of sparteine and derivatives we report herein how modification of sparteine at position 2 produces irreversible blockers of VGSCs. These compounds could be clinically envisaged as long-lasting local anesthetics., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The selective, metal-free generation of α-carbonyl cations from simple internal alkynes was accomplished by the addition of a sulfoxide to a densely substituted vinyl cation. The high reactivity of the α-carbonyl cations was found to efficiently induce hydrogen and even carbon shift reactions with unusual selecivities. Complex compounds with highly congested tertiary and all-carbon-substituted quartenary carbon centers can thus be accessed in a single step from simple precursors. Mechanistic analysis strongly supports the intermediacy of the title compounds and provides a simple predictive scheme for the migratory aptitude of different substituents., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The synthesis of α-amino carbonyl compounds is an important challenge in synthesis en route to biologically essential structures. While classical approaches involve the use of enol or enolate chemistries in combination with an electrophilic source of nitrogen, those strategies usually necessitate further transformations to reach the desired targets. In recent years, a new approach arose involving the direct use of nucleophilic sources of nitrogen along with an oxidant. This approach advantageously leads, in one-pot, to the biologically relevant α-amino compound without requiring further transformation. This review highlights the recent advances in the emerging field of oxidative α-amination reactions using nucleophilic sources of nitrogen., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The use of readily available hydroxamic acids as reagents for the chemoselective (ortho-amino)arylation of amides is described. This reaction proceeds under metal-free, mild conditions, displays a very broad scope, and constitutes a direct approach for the metal-free attachment of aniline residues to carbonyl derivatives., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Non-precious-metal-catalyzed reactions are of increasing importance in chemistry due to the outstanding ecological and economic properties of these metals. In the subfield of metal-catalyzed direct C-H functionalization reactions, recent years have shown an increasing number of publications dedicated to this topic. Nickel, cobalt, and last but not least iron, have started to enter a field which was long dominated by precious metals such as palladium, rhodium, ruthenium, and iridium. The present review article summarizes the development of iron-, nickel-, and cobalt-catalyzed C-H functionalization reactions until the end of 2016, and discusses the scope and limitations of these transformations., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Much contemporary organic synthesis relies on transformations that are driven by the intrinsic, so-called "natural", polarity of chemical bonds and reactive centers. The design of unconventionally polarized synthons is a highly desirable strategy, as it generally enables unprecedented retrosynthetic disconnections for the synthesis of complex substances. Whereas the umpolung of carbonyl centers is a well-known strategy, polarity reversal at the α-position of a carbonyl group is much rarer. Herein, we report the design of a novel electrophilic enolonium species and its application in efficient and chemoselective, metal-free oxidative C-C coupling., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A general, asymmetric redox arylation of ynamides and thioalkynes with chiral sulfoxides is reported. This is the first example of a general 1,4-chirality transfer from sulfur to a carbon stereocenter through a sulfonium [3,3]-sigmatropic rearrangement. This reaction delivers α-arylated thioesters and amides under mild conditions in an atom-economical manner. The products are formed in high yields with enantiomeric ratios up to 99.5:0.5. Quantum chemical calculations suggest a mechanism for the chirality transfer from sulfur to carbon and explain the experimentally observed correlation of the enantioselectivity with both the catalyst and the substrate., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

An efficient metal-free oxyarylation of electron-poor alkynes with pyridine N-oxides has been developed. This transformation affords meta-substituted pyridines analogous to the drug metyrapone in high regioselectivities. Density functional theory (DFT) calculations provided important insight into the mechanism. Evaluation of the inhibitory properties revealed the most active CYP11B1 inhibitor of these derivatives, with two-digit nanomolar inhibitory activity akin to that of metyrapone., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

8-Aminoquinoline has emerged as one of the most powerful bidentate directing groups in history of C-H activation within the last decade. However, cleavage of its robust amide bond has shown to be challenging in several cases, thus jeopardizing the general synthetic utility of the method. To overcome this limitation, we herein report a simple oxidative deprotection protocol. This transformation rapidly converts the robust amide to a labile imide, allowing subsequent cleavage in a simple one-pot fashion to rapidly access carboxylic acids or amides as final products., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The reaction of aryl-substituted allenes with alcohols under gold catalysis led to highly substituted indenes in good yields, with low catalyst loading and under mild conditions. During this domino transformation, two C-C bonds are formed with water as the only byproduct., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The synthesis of pyridines through direct intermolecular cycloaddition of alkynes and nitriles is a contemporary challenge in organic synthesis. A Brønsted acid mediated formal [2+2+2] cycloaddition of heteroalkynes and nitriles was developed that proceeds under mild conditions. This constitutes a modular approach to highly substituted pyridine cores., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel formal [3+2] cycloaddition of cyclopropylacetals and aldehydes was developed, and the resulting trisubstituted tetrahydrofurans display three new chiral centers formed with highly diastereoselectivity. This method is stereocomplementary to most previously reported cycloadditions of malonate diesters, relies on the transient generation of cyclopropyl oxocarbenium ions, proceeds under mild conditions, and is based on the concept of temporary activation of an otherwise inert protecting group., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)