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An organophosphine-controlled diversity-oriented synthesis of chromone inden-1-one-fused cyclopentadienylides and C-acylated 2-((chromone-3-yl)methylene)-indandiones is reported. Key attributes of the methodology are the in situ generation of an allylic P-ylide and subsequent regio- and chemoselective intramolecular cyclization reactions that preferentially result in the aforementioned chromone adducts. [ABSTRACT FROM AUTHOR]

A new series of N-benzyl-2,5-dihydro-1H-pyrrole-linked benzopyrimidines 5 and 6 were synthesized via the 1,3-dipolar cycloaddition reaction of acetylenic dipolarophiles 3 and 4 with azomethine ylide generated in situ from N-(methoxymethyl)-N-(trimethylsilyl)benzylamine and evaluated for their in vitro antimicrobial activity. The structures of the prepared products were characterized using 1H/13C NMR, IR, and ESI-HRMS techniques. Further, the synthesized compounds were assessed for their antibacterial activity against five types of pathogenic bacteria and three fungal strains. The results show that the degree of antimicrobial effect displayed by the synthesized compounds was variable. Notably, compounds 2a, 2d, 2f, 3e, 3h, 4a, 4d, 4f, 5a, 5b, 5d, 5f, 6b, and 6c showed high activity against the bacterial strains, with MIC values ranging from 15.12 to 15.62 μg mL−1. Moreover, compounds 2a, 2f, 5a, 5b, 5d, 5g, and 5h exhibited promising antifungal activity against three Candida strains, with MIC values ranging from 62.5 to 125 μg mL−1. In addition, molecular docking studies performed to identify the most effective antibacterial compounds against B. subtilis highlighted the high binding affinity of the synthesized compounds toward Bacillus subtilis YdiB (pdb: 5MVR). [ABSTRACT FROM AUTHOR]

We present a straightforward, catalyst- and additive-free method for synthesizing keto γ-butyrolactones using readily available β-keto sulfoxonium ylides and acrylic acids. This robust approach demonstrates exceptional compatibility with various functional groups on β-keto sulfoxonium ylides and α-substituted acrylic acids, resulting in good to high yields of the anticipated products. Moreover, the practicality of this approach was validated through large-scale reactions and the successful conversion of some synthesized derivatives into bioactive natural products, including L-factor, muricatacin, and cytosporanone A. [ABSTRACT FROM AUTHOR]

A Cu‐catalyzed multi‐component reaction of trifluoromethylated β‐amino ketones and nitriles using tert‐butyl nitrite as a diazotization reagent has been developed. Under the optimized conditions, N‐trifluoroalkyl amides were obtained with yields up to 87%. Control experiments and computational studies reveal that the reaction proceeds through the generation of diazo, in situ formation of nitrile ylide, water addition and final enol tautomerism. This approach features mild reaction conditions, wide substrate tolerance, and scale‐up applicability, which provides an efficient and practical strategy for amide synthesis. [ABSTRACT FROM AUTHOR]

An electrochemical protocol for the synthesis of sulfursulfoxonium ylides and 1,3-dithioketals by reacting sulfoxonium ylides with disulfides has been developed under simple and mild conditions. By changing the solubility of the raw materials and the dielectric parameters of the electrolyte, sulfurization enabled a selective dehydrogenation of C–S and the construction of 1,3-dithioketals. The transformation is an ideal approach to prepare organosulfur reagents with a broad functional group tolerance as well as high selectivity, which leads to vicinal difunctionalized organosulfur compounds. [ABSTRACT FROM AUTHOR]

The development of efficient synthetic strategies for the preparation of tetrasubstituted N−H pyrrole derivatives, especially in an environmentally benign fashion is important yet challenging. Herein, we report a copper(II)‐catalyzed tandem reaction involving 1,3‐dipolar cycloaddition of α,β‐ynones and glycine iminoesters, followed by copper(II)‐promoted oxidative (air) dehydrogenative aromatization, allowing de novo access to tetrasubstituted N−H pyrroles in up to 81 % yield under green reaction conditions. A possible reaction pathway is tentatively proposed. Finally, fully substituted pyrroles are available by N‐alkylation, and a preliminary phase‐transfer catalytic asymmetric N‐alkylation was also studied to give an axially chiral pyrrole. [ABSTRACT FROM AUTHOR]

Herein, we report a mild method for the synthesis of oxaspirocyclohexadienones by using a combination of Lewis acid‐HFIP mediated [2+3]‐annulation of p‐quinone methides (p‐QMs) and iodonium ylides. The proposed mechanism proceeds through a one‐pot sequence of carbonyl activation/cyclopropyl formation/Cloke‐Wilson rearrangement to provide a broad range of oxaspirocyclohexadienones in moderate to high yields. Interestingly, the spiro‐annulated products were further converted to tetrahydroxanthane derivatives via BF3.OEt2 mediated dienone‐phenol rearrangement pathway. Moreover, the spiro‐annulated derivatives also showed a moderate anti‐tuberculosis activity against Mycobacterium tuberculosis H37Ra ATCC25177. [ABSTRACT FROM AUTHOR]

Synthesis of new polysubstituted furans incorporating reactive phosphorus ylides or N‐acyliminophosphoranes was achieved by the heterocyclization of flexible α‐acyl ketene dithioacetals. This one‐pot tandem reaction was initiated by acyl‐directed desulfurative Sonogashira coupling, followed by 1,6‐addition of phosphine to the in situ‐generated enynone and subsequent 5‐exo‐dig cyclization, as well as phosphoranation. The selectivity toward the two products, i. e. α‐phosphorus ylides vs. α‐N‐acyliminophosphoranes‐substituted furans, was determined by both electron‐deficient acetylenes and copper salts. [ABSTRACT FROM AUTHOR]

Herein, we report a regioselective cycloaddition strategy of N -aminopyridinium ylides with electron-deficient alkenes, in the presence of a hypervalent iodine reagent, PhI(OAc)2. A variety of multifunctionalized pyrazolo[1,5- a ]pyridine architectures were smoothly afforded by the reactions of pyridine-, quinoline-, and isoquinoline-based N -ylides with diverse alkenes with or without a halogen atom adjacent to the electron-withdrawing group (EWG) under facile conditions. [ABSTRACT FROM AUTHOR]

Thanks to the ability of diazo derivatives to react either as 1,3‐dipoles and as carbenes after dinitrogen extrusion, combinations of oxa or aza benzonorbornadienes and diazomalonates afford polycyclic pyrazolidines via a three‐step sequence of (i) a highly diastereoselective [3+2]‐cycloaddition, (ii) a CpRu‐catalyzed carbene addition, and (iii) a second dipolar cycloaddition. Of importance, step (II) represents a unique access to novel bench‐stable N,N‐cyclic azomethine imines, which behave as effective 1,3‐dipoles in combination with electron‐poor dipolarophiles. Each step proceeds efficiently and the 3‐step process can be performed in one‐pot to yield a polycyclic pyrazolidine in excellent overall yield (90 %). [ABSTRACT FROM AUTHOR]

Transition-metal-catalyzed directed C–H functionalization with various carbene precursors has been widely employed for constructing a wide range of complex and diverse active molecules through metal carbene migratory insertion processes. Among various carbene precursors, iodonium ylides serve as a novel and emerging carbene precursor with features including easy accessibility, thermal stability and high activity, which have attracted great attention from organic chemists and have achieved tremendous success in organic transformation. In this review, recent progress on the application of iodonium ylides with multifunctional coupling characteristics in C–H bond activation reactions is summarized, and the potential of iodonium ylides is discussed. [ABSTRACT FROM AUTHOR]

4′-Nitro-2 H -spiro[acenaphthylene-1,2′-pyrrolidine]-2-one derivatives are prepared via [3+2] cycloaddition reactions of azomethine ylides, generated in situ from acenaphthoquinone and primary amines, with β-nitrostyrenes in the presence of (i Pr)2 NEt in methanol. Evidence for the structures of the products was obtained from single-crystal X-ray analysis. The important feature of this diastereoselective synthesis of NH-unprotected spiropyrrolidines is the formation of four contiguous stereogenic centers, one of which is quaternary, with high selectivity. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal Chemical Communications. It provides a list of articles and their authors that are featured in the journal's latest issue. The articles cover a range of topics in the field of chemistry, including electrocatalytic water-to-oxygen conversion, catalyst development for oxidative dehydrogenation, and photomechanical properties in metal-organic crystals. The journal aims to connect the global chemistry community and invest its profits back into the field. [Extracted from the article]

Pyridyloxy-directed Ir(III)-catalyzed diacylmethylation of protected tyrosines was achieved with alkyl and (hetero)aryl sulfoxonium ylides, furnishing tyrosine-based unnatural amino acids in good yields. Furthermore, the late stage exemplification of the strategy was successfully accomplished in tyrosine-containing dipeptides, tripeptides and tetrapeptides in moderate yields. This methodology is distinguished by its site-selectivity, tolerance of sensitive functional groups, scalability, and retention of the chiral configuration for tyrosine motifs. [ABSTRACT FROM AUTHOR]

Transition metal‐catalyzed epoxidation of carbonyl compounds through carbonyl ylides represents a highly effective method for synthesizing a diverse range of valuable epoxides. This review offers an in‐depth overview of the latest developments in inter‐ and intramolecular epoxidation reactions involving metal carbenes and carbonyl compounds, encompassing both racemic to enantioselective transformations. These catalytic epoxidations are reviewed by highlighting their product selectivity, diversity and applicability, and the related mechanistic rationale is showcased where possible. [ABSTRACT FROM AUTHOR]

Sulfo(xo)nium diacylmethylides (sulfur ylides) are simple, stable, readily prepared, and versatile synthons. Compared with the sulfo(xo)nium monoacylmethylides, they can be compatible with more rigorous reaction conditions and showcase unique characteristics due to their excellent stability. This concept article provides an account for the syntheses of sulfo(xo)nium diacylmethylides, including the utilization of active methylene compounds, carbene precursors, sulfo(xo)nium monoacylmethylides, and electron‐deficient alkynes as substrates, with discussions on substrate scopes, proposed mechanisms, selected product examples, and applications. Challenges for further exploration and prospect on sulfo(xo)nium diacylmethylides in the future are also suggested. [ABSTRACT FROM AUTHOR]

This article explores the advancements in stereodivergent carbon-carbon bond-forming reactions in organic chemistry. These reactions allow for the control of multiple stereogenic centers in a reaction, providing synthetic chemists with more flexibility and efficiency in constructing complex molecular structures. The article emphasizes the importance of these methods in drug discovery, where different stereoisomers of a drug can have different biological activities. The field of stereodivergent catalysis has grown significantly, with mono-catalytic and bifunctional catalytic methods contributing to the development of these reactions. Dual catalysis faces challenges, but progress has been made in finding compatible reaction types. The ultimate challenge lies in achieving high yields of multiple stereoisomers, but advancements in high-throughput experimentation and catalyst optimization may help overcome this challenge. [Extracted from the article]

Catalyst-free annulations of 2-(4H-benzo[d][1,3]oxazin-4-yl)acrylates have been successfully achieved under mild conditions. Specifically, the reaction of 2-(4H-benzo[d][1,3]oxazin-4-yl)acrylates with sulfur ylides furnished various 1,2-dihydroquinolines in generally high yields. Furthermore, [3+2]-annulations of 2-(4H-benzo[d][1,3]oxazin-4-yl)acrylates with α,β-unsaturated imines afforded a broad scope of polysubstituted 2,3-dihydropyrroles with high efficiency. [ABSTRACT FROM AUTHOR]

A new series of ligand precursors designed for the synthesis of palladalactams has been developed. These precursors are easily accessible through a one-step reaction involving 2-chloro-N-phenylacetamide and a wide choice of various monophosphines, offering tunable electronic and steric properties within the ligand framework. The stability of both ligand precursors and resulting palladalactams in ambient air enhances their practical applicability. A newly synthesized palladalactam, featuring an electron-donating triethylphosphine moiety on the anionic phosphonium ylide ligand scaffold exhibited promising catalytic activities in the Mizoroki–Heck coupling reaction between aryl chlorides and alkenes. Theoretical calculations further affirmed that the ligand system in the complex is the most electron-donating, forming the strongest Pd–C bond compared to other complexes with alternative phosphine moieties. [ABSTRACT FROM AUTHOR]

The first synthesis of well‐defined poly(methylene‐co‐1,1‐diphenylpropenenylene) (C1‐co‐C1'), equivalent to poly(ethylene‐co‐diphenylbutadiene) copolymers was accomplished by C1 copolymerization of novel diphenylpropenyl triphenyl arsonium ylides (Ph2AY) and dimethylsulfoxonium methylide (Me2SY) using B‐thexylborepane as initiator. All polymerization conditions, including feed ratio, temperature, and reaction time, were optimized. A series of photoluminescent poly(ethylene‐co‐diphenylbutadiene)s were synthesized at different feed ratios, opening a new synthetic horizon for poly(ethylene‐co‐disubstitutedbutadiene) copolymers. Notably, a new C1 segment, arising from a double bond rearrangement, was confirmed by NMR, resulting in an unprecedented two‐monomer three‐structure random terpolymer. An unexpected red‐shift phenomenon in the fluorescence spectra was observed with increasing the ratio of Ph2AY in the copolymer. This shift is attributed to the aggregation of diphenylbutadiene segment, similar to through‐space conjugation (TSC), likely induced by a decrease in the crystallinity of copolymers. Furthermore, another disubstituted allylic triphenyl arsonium ylides, (E)‐2‐phenylbutenyl triphenyl arsonium ylide (MePhAY) was also synthesized and investigated. These additional compounds expand the knowledge and the potential applications of such copolymerization techniques in advanced materials. [ABSTRACT FROM AUTHOR]

In this study, a Rh(III)-catalyzed C–H/N–H [4+2] annulation of oxadiazolones with iodonium ylides has been developed, which afforded a series of diverse fused-isoquinolines and fused-pyridines in moderate to high yields. These divergent synthesis protocols featured mild conditions, broad substrate scope, and functional-group compatibility. In addition, scale-up synthesis, related applications and preliminary mechanistic explorations were also accomplished. [ABSTRACT FROM AUTHOR]

The present personalized account summarizes various cyclization reactions, including multicomponent and domino processes, which are directed towards the synthesis of complex heterocyclic products. Domino Knoevenagel/hetero‐Diels‐Alder reactions provide a synthesis of annulated quinol‐2‐ones. The combination of Knoevenagel reactions with [3+2] cycloadditions of nitrogen ylides afford complex spiroheteriocyclic products. Domino Knoevenagel/enamine cyclization reactions result in the formation of condensed purine analogues. Formal [3+3] cyclizations of pyridinium salts allow for a rapid assembly of bridged heterocyclic systems and include the employment of thioxindoles and cyclohexane‐1,3‐diones as dinucleophilic building blocks. The formal [3+3] cyclization of thioxindoles with fluoroaroyl chlorides, such as 2‐fluorobenzoyl chlorides and 2‐chloropyridine‐3‐carboxylic chloride, give rise to the synthesis of condensed benzothiophenes. The cyclization of heterocyclic enamines with diimines and triazines afford various purine analogues by domino [4+2]/retro [4+2] reactions. The formal [3+3] cyclization of 2,4,6‐tris(trifluoromethyl)‐1,3,5‐triazine with 1,3‐bis(silyloxy)‐1,3‐butadienes afford, depending on the conditions, 2,6‐bis(trifluoromethy)pyrid‐4‐ones or triazaadamantanone derivatives. Heating of 2‐ethynylpyridines with electron‐rich dienes afforded 2‐(2‐methoxyphenyl)pyridines by a domino [4+2]/retro [4+2] process. The reaction of 2‐ethynylpyridines with enones afforded indolizines by a formal [3+3] cyclization. The reaction of trifluoromethyl‐substituted 1,3‐diketones with lithiated alkynes afforded 3‐hydroxy‐pent‐4‐yn‐1‐ones. Formal [5+1] cyclization of the latter with urea afforded trifluoromethyl‐substituted pyridines. The Pd catalyzed formal [3+2] cyclizations of 2,3‐dihalopyridines with imines afforded a series of regioisomeric 4‐ and 7‐azaindoles. [ABSTRACT FROM AUTHOR]

This article presents a new method for synthesizing 2,4-disubstituted oxazoles, which are important compounds with pharmaceutical and therapeutic activities. The authors describe a simple and efficient procedure using readily available materials and a copper catalyst. They successfully synthesized oxazoles with different functional groups in moderate to good yields. The method has potential applications in drug synthesis and ligand synthesis. [Extracted from the article]

In the past, the use of nitrogen ylides focused primarily on cycloadditions, where the 1,3‐dipole was used as a building block for the formation of heterocycles such as pyrroles or pyrrolinones. In this work, we present a new perspective on imidazolium dicyanomethylides with their synthesis and utilization as anionic N‐heterocyclic carbenes (NHCs). The values of relative carbene formation energies (CREF) for a wide range of substituted imidazolium ylides unknown in the literature showed promising properties. In situ trapping reactions of these anionic NHCs with selenium led to anionic, water‐soluble compounds that exhibited remarkable coordination behavior according to X‐ray structure analyses. In addition, the 77Se shifts of the investigated compounds were measured to draw conclusions about their π‐acceptance. [ABSTRACT FROM AUTHOR]

The reaction mechanism of tthe formation of azomethine ylides from isatins and sarcosine is addressed in the literature in a general manner. This computational study aims to explore the mechanistic steps for this reaction in detail and to assess the reactivity of formed ylide in a 1,3-dipolar cycloaddition reaction with 7-oxabenzonorbornadiene. For this purpose, density functional theory (DFT) calculations at the M06-2X(SMD,EtOH)/6-31G(d,p) level were employed. The results indicate that CO2 elimination is the rate-determining step, the activation barrier for 1,3-dipolar cycloaddition is lower, and the formed ylide will readily react with dipolarophiles. The substitution of isatine with electron-withdrawal groups slightly decreases the activation barrier for ylide formation. [ABSTRACT FROM AUTHOR]

The addition of PnBu3 to o-substituted dianiline squaraine dyes leads to bench stable ylides. Exposure to a metal analyte in solution, results in PIII abstraction and rapid disruption of the ylide conjugation to promote reversion back to the squaraine dye giving an immediate turn-on colorimetric response. The stoichiometric sensitivity and accessibility of these chemodosimeters constitute effective organic dyes for trace transition metal detection. [ABSTRACT FROM AUTHOR]

Visible-light-induced [3+2] cyclization of vinyl azides with perfluoroalkyl-substituted imidoyl sulfoxonium ylides has been developed for the first time. In this transformation, perfluoroalkyl-substituted imidoyl sulfoxonium ylides are firstly employed as a carbon radical precursor under visible light irradiation, providing a new and efficient method for the construction of perfluoroalkyl-substituted 1-pyrrolines. [ABSTRACT FROM AUTHOR]

N‐Heterocyclic ylides are important synthetic precursors to rapidly build molecular complexity. Pyrazolium ylides have largely been unexplored, and we demonstrate their diverse utility in this report. We show that these readily accessible building blocks can be used to construct different heterocyclic skeletons by varying the coupling partner. Indolizines can be formed via an N‐deletion type mechanism when reacting pyrazolium salts with electron deficient alkynes. 1,2‐Dihydropyrimidines can be formed via a rearrangement mechanism when reacting pyrazolium ylides with isocyanates. These reactions enable access to valuable heteroarenes without the need for transition metal catalysis, high temperatures, or strong bases. [ABSTRACT FROM AUTHOR]

The article introduces a disposable monolithic column mass spectrometry analysis kit for direct whole blood analysis, offering rapid cleaning and protection of samples, proven effective for quantifying procainamide hydrochloride in rat blood. Topics include the synthesis of functional dibenzoullazines, guaiane-type sesquiterpenoid trimers' discovery, and immobilization of triphenylamine for photocatalytic oxidation of thiols to disulfides.

Comprehensive Summary: A new family of dibenzoullazine derivatives was synthesized through 1,3‐dipolar cycloaddition of polycyclic aromatic azomethine ylides with alkynylbenziodoxoles followed by oxidation. The benziodoxole moiety in the resulting products was used as a versatile linchpin for the synthesis of structurally diverse functional dibenzoullazines that are difficult to access by other synthetic methods. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A new family of dibenzoullazine derivatives was synthesized through 1,3‐dipolar cycloaddition of polycyclic aromatic azomethine ylides with alkynylbenziodoxoles followed by oxidation. The benziodoxole moiety in the resulting products was used as a versatile linchpin for the synthesis of structurally diverse functional dibenzoullazines that are difficult to access by other synthetic methods. [ABSTRACT FROM AUTHOR]

Cumulenes and heterocumulenes with three or more cumulative multiple bonds are usually reactive species that serve as valuable building blocks for more complex molecules but tend to isomerize or cyclize and therefore are difficult to isolate. Using a mild ligand exchange reaction at the carbon in α‐metalated ylides, we have now succeeded in the synthesis and gram‐scale isolation of the elusive cyanoketenyl anion [NC3O]−. Despite its assumed cumulene‐like structure and the delocalization of the negative charge across the whole 5‐atom molecule, it features a bent geometry with a nucleophilic central carbon atom. Computational studies reveal an ambiguous bonding situation in the anion, which can be illustrated only by a combination of different resonance structures. Nonetheless, the anion features remarkable stability, thus allowing the storage of its potassium‐crown ether salt and its application as a highly functional synthetic building block. The cyanoketenyl anion readily reacts with a series of small molecules to form more complex organic compounds, including industrially valuable compounds such as cyanoacetate. This work demonstrated that reactive species can be generated by novel synthesis methods and open up atom‐economic pathways to complex compounds from small abundant molecules. [ABSTRACT FROM AUTHOR]

Cumulenes and heterocumulenes with three or more cumulative multiple bonds are usually reactive species that serve as valuable building blocks for more complex molecules but tend to isomerize or cyclize and therefore are difficult to isolate. Using a mild ligand exchange reaction at the carbon in α‐metalated ylides, we have now succeeded in the synthesis and gram‐scale isolation of the elusive cyanoketenyl anion [NC3O]−. Despite its assumed cumulene‐like structure and the delocalization of the negative charge across the whole 5‐atom molecule, it features a bent geometry with a nucleophilic central carbon atom. Computational studies reveal an ambiguous bonding situation in the anion, which can be illustrated only by a combination of different resonance structures. Nonetheless, the anion features remarkable stability, thus allowing the storage of its potassium‐crown ether salt and its application as a highly functional synthetic building block. The cyanoketenyl anion readily reacts with a series of small molecules to form more complex organic compounds, including industrially valuable compounds such as cyanoacetate. This work demonstrated that reactive species can be generated by novel synthesis methods and open up atom‐economic pathways to complex compounds from small abundant molecules. [ABSTRACT FROM AUTHOR]

Cumulenes and heterocumulenes with three or more cumulative multiple bonds are usually reactive species that serve as valuable building blocks for more complex molecules but tend to isomerize or cyclize and therefore are difficult to isolate. Using a mild ligand exchange reaction at the carbon in α‐metalated ylides, we have now succeeded in the synthesis and gram‐scale isolation of the elusive cyanoketenyl anion [NC3O]−. Despite its assumed cumulene‐like structure and the delocalization of the negative charge across the whole 5‐atom molecule, it features a bent geometry with a nucleophilic central carbon atom. Computational studies reveal an ambiguous bonding situation in the anion, which can be illustrated only by a combination of different resonance structures. Nonetheless, the anion features remarkable stability, thus allowing the storage of its potassium‐crown ether salt and its application as a highly functional synthetic building block. The cyanoketenyl anion readily reacts with a series of small molecules to form more complex organic compounds, including industrially valuable compounds such as cyanoacetate. This work demonstrated that reactive species can be generated by novel synthesis methods and open up atom‐economic pathways to complex compounds from small abundant molecules. [ABSTRACT FROM AUTHOR]

Cumulenes and heterocumulenes with three or more cumulative multiple bonds are usually reactive species that serve as valuable building blocks for more complex molecules but tend to isomerize or cyclize and therefore are difficult to isolate. Using a mild ligand exchange reaction at the carbon in α‐metalated ylides, we have now succeeded in the synthesis and gram‐scale isolation of the elusive cyanoketenyl anion [NC3O]−. Despite its assumed cumulene‐like structure and the delocalization of the negative charge across the whole 5‐atom molecule, it features a bent geometry with a nucleophilic central carbon atom. Computational studies reveal an ambiguous bonding situation in the anion, which can be illustrated only by a combination of different resonance structures. Nonetheless, the anion features remarkable stability, thus allowing the storage of its potassium‐crown ether salt and its application as a highly functional synthetic building block. The cyanoketenyl anion readily reacts with a series of small molecules to form more complex organic compounds, including industrially valuable compounds such as cyanoacetate. This work demonstrated that reactive species can be generated by novel synthesis methods and open up atom‐economic pathways to complex compounds from small abundant molecules. [ABSTRACT FROM AUTHOR]

The construction of N-fused polycyclic compounds at room temperature via the combination of transition-metal catalyst and photocatalyst has been reported. This novel work has successfully realized LED irradiated C-H activation of iodonium ylides. The strategy shows wide substrate scope and ideal functional group tolerance. Our work would be useful for the construction of various heterocyclic compounds. [ABSTRACT FROM AUTHOR]

The study investigated the reactivity of various CH-acids/conjugated bases in the synthesis of hepta(methoxycarbonyl)cycloheptatriene through a cascade reaction. NMR spectral monitoring identified (methoxycarbonyl)methylpyridinium as the true nucleophilic component in the original synthesis based on methyl diazoacetate. The scope of CH-acids capable of participating in the reaction was expanded to include sulfonium salts and sulfones, whereas certain nucleophiles were found to be ineffective. A correlation between the pKa values of CH-acids and the formation of seven-membered rings in the cascade reaction was established. [ABSTRACT FROM AUTHOR]

A metal‐free [4+1] annulation of in‐situ generated ortho‐quinone methides (o‐QMs) and CF3−imidoyl sulfoxonium ylides (TFISYs) has been achieved under mild conditions, which provides a facile and straightforward access to a variety of trifluoromethyl‐containing 2,3‐dihydrobenzofurans in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

A novel method was devised for regioselective ring expansion of Meldrum's acid-derived spirocyclopropanes to spirocyclobutanes with stabilized sulfonium ylides, affording 1,2-trans-disubstituted 6,8-dioxaspiro[3.5]nonane-5,9-diones in up to 87% yields without the formation of any isomers. The aforementioned reaction was also applied to the barbituric acid-derived spirocyclopropane, resulting in the formation of the corresponding cyclobutanes. [ABSTRACT FROM AUTHOR]

The transmetalation triggered rhodium‐catalyzed C−H bond activation and tandem annulation of 2‐biphenylboronic acids with sulfoxonium ylides or iodonium ylides has been developed. Various products of phenanthrenes were constructed under redox‐neutral conditions in 34–86% yields. Several mechanism exploration experiments and derivatization reactions were conducted in sequence to gain a deeper understanding of the process and the potential of this transformation. It offers an alternative approach for the synthesis of phenanthrene derivatives. [ABSTRACT FROM AUTHOR]

To date, it remains challenging to achieve a general and catalytic α‐arylation of cyclic 1,3‐dicarbonyls, particularly ubiquitous heteroaromatic ones. In most cases, the preparation of their medically significant arylated derivatives requires multistep synthetic sequences. Herein, we introduce a new, convenient strategy involving the conversion of cyclic 1,3‐dicarbonyls to cyclic iodonium ylides (CIYs), followed by rhodium‐catalyzed α‐arylation with arylboronic reagents via carbene coupling. This approach is mild, operationally simple, base‐free, biocompatible, and exhibits broad substrate scope (>100 examples), especially with respect to various heteroaromatic 1,3‐dicarbonyls and ortho‐substituted or base‐sensitive arylboronic acids. Importantly, owing to the excellent compatibility with various arylboronic acids or boronate esters (ArBpin, ArBneop, or ArBF3K), this method allows the late‐stage installation of heterocyclic 1,3‐dicarbonyl motifs in highly complex settings. The utility of this transformation is further demonstrated through significantly simplifying the synthesis of several bioactive molecules and natural products. [ABSTRACT FROM AUTHOR]

Organic molecules containing fluorine and sulfur atoms represent a large percentage of approved pharmaceuticals. Those with combination of both S and F atoms in their structure such as Xtandi, approved in 2012 for prostate cancer, indicates the importance of synthetic methods that accommodates both atoms in an organic moiety. In this study, a novel aspect of sulfoxonium ylide reactivity was explored, unveiling a streamlined and mild synthesis method for gem‐difluorinated keto‐sulfoxides. Our protocol offers a direct and practical approach to prepare these compounds in 14–80 % chemical yields, that were represented by 21 examples. NMR studies and Hammett correlations gave strong evidence about the mechanism of this transformation. [ABSTRACT FROM AUTHOR]

The development of stereoselective olefination using sulfur ylidederived vinyl carbenes with diazo esters and acetals is reported. Both reactions proceed through nucleophilic addition to electrophiles at the γ-position of an in situ-generated 2-alkoxy furan intermediate. The synthetic utility of the developed method is demonstrated by the total synthesis of rubrolide E. Detailed mechanistic investigations and quantum chemical calculations provide insight into the reaction mechanism. [ABSTRACT FROM AUTHOR]

This article presents a study on the synthesis of pyrido[1,2-a:4,3-b']diindoles through a ruthenium-catalyzed coupling/cyclization reaction. The researchers investigated the reaction conditions and found that electron-donating groups and certain substitutions on the indole ring were well tolerated, resulting in good yields of the desired products. The proposed reaction pathway involves the formation of a ruthenacycle intermediate, followed by the insertion of a sulfur ylide and subsequent cyclization. The authors suggest that these pyrido[1,2-a:4,3-b']diindole derivatives may have potential pharmaceutical applications. [Extracted from the article]

A three-component organocatalytic reaction of 1,3-dipolar cycloaddition between the in situ generated azomethine ylides and 3-substituted 1,2-diphenylcyclopropenes is described. The azomethine ylides have been generated via condensation of aromatic compounds (such as isatins and acenaphthenequinone) with benzylamines. The reaction has afforded derivatives of 3-azabicyclo[3.1.0]hexane, spiro-fused with the fragments of 2-oxindole and acenaphthylene-1(2H)-one. The cycloadducts have been obtained with yield up to 91%, mainly as individual diastereomers. The influence of bifunctional squaramide-based organocatalysts on the course of these three-component reactions has been investigated. Antiproliferative activity of selected synthesized compounds with respect to the human erythromyelosis (K562) and melanoma (Sk-mel-2) cell lines has been assessed in vitro by means of MTS analysis. [ABSTRACT FROM AUTHOR]

A one‐pot three component reaction of benzotriazolium ylides, aldehydes or ketones, and 1,3‐dicarbonyl compounds has been developed for the synthesis of activated tetra‐ and penta‐substituted cyclopropanes. The transformation features high reactivity and diastereoselectivity, broad substrate scope, room temperature, and simple operation. [ABSTRACT FROM AUTHOR]

Mono‐ and bis‐pyridinium, phosphonium and sulfonium allylic salts, containing adamantane fragment, have been obtained from the substitution reaction in 1,4‐dibromo‐2‐butene. It was found, that the attack of triethylamine undergoes from the sterically less hindered side, leading to deprotonation and subsequent elimination of the molecular fragment with the formation of a new salt of diene structure. Quantum chemical calculations were used to confirm the structure of one of the products by correlation analysis of experimental and calculated NMR data that confirmed the s‐cisoid conformation of the diene. It was found, that obtained dienes may be used as substrates in Diels‐Alder reaction despite their high sterical hinderance. [ABSTRACT FROM AUTHOR]

This manuscript describes the development of alkyne addition to the aziridine moiety of aziridinoquinoxalines using dual Ir(III)/Cu(I) catalytic system under green light‐emitting diode (LED) photolysis (λmax=525 nm). This mild method features high levels of chemo‐ and regioselectivity and was used to generate 30 highly functionalized substituted dihydroquinoxalines in 36–98 % yield. This transformation was also carried asymmetrically using phthalazinamine‐based chiral ligand to provide 9 chiral addition products in 96 : 4 to 86 : 14 e.r. The experimental and quantum chemical explorations of this reaction suggest a mechanism that involves Ir(III)‐catalyzed triplet energy transfer followed by a ring‐opening reaction ultimately leading to the formation of azomethine ylide intermediates. These azomethine intermediates undergo sequential protonation/copper(I) acetylide addition to provide the products. [ABSTRACT FROM AUTHOR]

This article introduces a special collection of papers dedicated to Maurizio Prato, a renowned scientist in the field of carbon nanostructures and molecular nanoscience. The collection showcases Prato's team's achievements in integrating complex frontier research with groundbreaking advancements in these fields. Prato's work focuses on designing and synthesizing carbon nanostructures for applications in regenerative medicine and solar energy research. The article highlights Prato's scientific journey, his contributions to sustainable materials, and his impact on shaping functional nano-interfaces through precision chemistry. The Prato lab has made significant contributions to nanotechnology, particularly in the area of functionalized carbon nanotubes (f-CNT). Their research has shown that f-CNT are more biocompatible and easily cleared from the body compared to nonfunctionalized CNT. The lab has applied this knowledge to develop solutions for challenging problems such as healing spinal cord injuries and using water as a solar fuel. Their work in regenerative medicine has shown promising results in repairing severe and irreversible nervous system lesions, while their research in energy conversion has explored the use of f-CNT for solar energy conversion. Maurizio Prato, the leader of the lab, has fostered an interdisciplinary and collaborative environment, encouraging his team to explore diverse research avenues and promoting intellectual freedom. His mentorship and open-mindedness have been instrumental in the lab's success. [Extracted from the article]

A catalyst system based on palladium 2‐methylnaphthyl complexes bearing ylide‐functionalized phosphines (YPhos) was found to enable the selective γ‐arylation of 1,3‐dioxinone derivatives with diversely functionalized aryl, heteroaryl, and vinyl chlorides. The products were further converted into 1,3‐diketones and heterocycles, highlighting their function as synthetic hubs. Experimental and computational studies revealed that bulky, electron‐rich YPhos ligands are uniquely effective because they enable the oxidative addition of aryl chlorides at room temperature while at the same time efficiently promoting the rate‐limiting reductive elimination step of the thermally sensitive enolates. [ABSTRACT FROM AUTHOR]