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Diastereoselective (3+3) cycloaddition between bicyclobutanes and pyridinium ylides forms azabicyclo[3.1.1]heptanes via pyridine dearomatization. These reactions proceed under ambient conditions with no need for photochemistry or catalysis, and tolerate a wide range of functional gorups. The resulting multicyclic ring systems have diverse synthetic handles for further transformations, making them potentially valuable for the design of Csp³-rich drug candidates. These include semi-reduction of the dihydropyridine, and diastereoselective photochemical skeletal rearrangement to give a tetrasubstituted cyclobutane. [ABSTRACT FROM AUTHOR]

The Chemical Communications journal, published by The Royal Society of Chemistry, features articles on various topics such as advances in oxygen catalysis, total synthesis of natural products, and the synthesis of different chemical compounds. The journal also covers research on batteries, energy storage, and the development of new materials for various applications. The articles in this issue highlight recent advancements in the field of chemistry and showcase innovative research in the chemical sciences. [Extracted from the article]

The present work reveals a new metal-catalyzed synthetic reaction involving 1,2,3-benzotriazinones with carbonyl sulfoxonium ylide and iodonium ylide, resulting in divergent products. Within this catalytic system, 3-phenylbenzo[d][1,2,3]triazin-4(3H)-one derivatives undergo C–H alkylation processes facilitated by a Cp*Rh(III) catalyst when combined with a carbonyl sulfoxonium ylide. On the other hand, when iodonium ylide substrates are used, they undergo an alkenylation reaction facilitated by a Cp*Ir(III) catalyst. In addition, hydrazone products are produced by synthesizing iodonium ylide substrates with the use of a copper catalyst. These transformations demonstrate mild reaction conditions, a wide range of substrates, and excellent compatibility with various functional groups. The strategy and tactics utilized have been effectively implemented on a significant scale. [ABSTRACT FROM AUTHOR]

A Brønsted acid-mediated insertion of thioureas/thioamides into sulfoxonium ylides to synthesise 40 thiazoles (34–95% yields) under mild, metal-free conditions is described. This process is scalable, substrate-tolerant (including both α-substituted and heterocyclic ylides/groups) and was successfully applied to the late-stage functionalisation of the complex chemical probe molecule (+)-JQ1. [ABSTRACT FROM AUTHOR]

We propose a [4+1] annulation of sulfoxonium ylides with allyl ethers catalyzed by Rh(III), which leads to the formation of alkyl-substituted indanone derivatives. The reactions occur under mild conditions without external oxidants. The ylide serves as a traceless directing group in the subsequent annulation with allyl alkyl ethers via the (4+1) annulation. The process involves Csp2–H bond functionalization facilitated by AgBF4, generating DMSO as a separable byproduct. This redox–neutral reaction exhibits a good substrate scope and excellent yields toward the various alkyl allyl ethers. The molecular structures of the title compounds (3a, 3b, and 3c) are optimized at the DFT/B3LYP/6-311++G(d,p) level of the basis set. The hyperpolarizability (β0) values that are computed suggest that all molecules may behave in a nonlinear optical (NLO) manner. The Lewis (bonding) and non-Lewis (anti-bonding) structural types are calculated to investigate the intramolecular charge transfer inside the molecule. It appears that the molecule experiences intramolecular charge transfer based on the HOMO–LUMO transition. Understanding a molecule's reactive sites is possible by using its molecular electrostatic potential (MEP) surface. At various temperatures in the gas phase, the thermodynamic parameters of the title compounds, including entropy, heat capacity, and enthalpy, are calculated. Additionally, the anti-inflammatory and anti-diabetic performances of the above-synthesized compounds revealed better activity than their standard drug molecules. [ABSTRACT FROM AUTHOR]

The synthesis of acylmethylatated pyrrolo‐quinazolinones was developed via photo‐induced cascade radical addition/cyclization of N‐(but‐3‐enyl)quinazolin‐4(3H)‐ones with sulfoxonium ylides using 4CzIPN as the photocatalyst. This approach was also suitable for the construction of acylmethylatated piperidino‐quinazolinones. This protocol features with mild conditions, convenient operation, broad substrate scope and good functional group compatibility. [ABSTRACT FROM AUTHOR]

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]

We report herein a reexamination of the reactions between sulfoxonium ylides and acetylenic esters. Continuing our previous study of conjugate additions using α‐carbonyl sulfoxonium ylides, we came across an interesting transformation when dimethyl acetylenedicarboxylate (DMAD) was employed as a Michael acceptor. Trisubstituted electron‐deficient 1,3‐dienes and α‐carbonyl vinyl sulfoxides were obtained for the first time from these sulfur ylides, in a stereoselective manner (exclusively forming the E‐isomer), achieving yields of up to 70 % and 83 %, respectively. Selected dienes were subsequently utilized in the synthesis of novel nitrogen heterocycles. Interestingly, when di‐tert‐butyl acetylenedicarboxylate (DtBAD) or alkyl propiolates were evaluated, the isolated product arose from the classical Michael addition, yielding α‐carbonyl vinyl sulfoxonium ylides in yields of up to 89 %. [ABSTRACT FROM AUTHOR]

A three‐component allylic alkylation reaction of α‐diazo ketones, water and allyl carbonate under the cooperative catalysis of Rh2(OAc)4, Pd2(dba)3 and Brønsted acid was disclosed. This method provides an expeditious access to α‐keto homoallylic alcohols in good to high yields. Controlled experiments support that the transformations proceed through cross‐interception of two active intermediates Pd‐allyl species and enol intermediates derived from oxonium ylides. Moreover, synthetic transformations of the generated products enable the creation of motifs enriched with dense functional groups, underscoring their potential as valuable building blocks. [ABSTRACT FROM AUTHOR]

The synthesis of two stable monoylide‐substituted stannylenes of type YCNSnR [R=Cl (1) or N(SiMe3)2 (2), and YCN=Ph3P(CN)C] starting from the cyanido‐substituted α‐metallated ylide YCN–K and SnCl2 or (SiMe3)2NSnCl is reported. Coordination of the cyano group to the tin center results in the dimerization of both stannylenes 1 and 2 in the solid state as well as in solution, where syn‐ and anti‐isomers are present. X‐ray diffraction analyses in combination with DFT calculations revealed that the π‐electron density of the ylide ligand is predominantly shifted into the cyano moiety rather than towards the tin center. This results in a strong preference of the dimers over the monomers, which is further emphasized by the reaction with 2,5‐di‐tert‐butylhydroquinone, which undergoes a [1+4] addition to the tin center to yield a spiro compound while preserving the cyclic core of the dimer. In contrast, phenyl isocyanate and dicyclohexylcarbodiimide insert into the Sn−Cylide bond, ultimately leading to the cleavage of the dimer and the formation of monomeric stannylenes with an ylide‐substituted thioamidato and amidinato ligand, respectively. [ABSTRACT FROM AUTHOR]

The isolation and catalytic enantioselective synthesis of configurationally stable S‐stereogenic sulfonium ylides have been significant challenges in the field of asymmetric synthesis. These reactive intermediates are crucial for a variety of synthetic transformations, yet their inherent tendency towards rapid inversion at the sulfur stereocenter has hindered their practical utilization. Conventional approaches have focused on strategies that incorporate a C=S bond‐containing cyclic framework to help mitigate this stereochemical lability. In this work, we present an alternative tactic that leverages the stabilizing influence of an adjacent N‐atom and cyclic sulfide moiety. Exploiting a copper catalyzed enantioselective intermolecular carbene transfer reaction, structurally diverse S‐stereogenic aminosulfonium ylides have been achieved in excellent yields and enantioselectivities. Experimental results indicate that the careful selection of 2‐diazo‐1,3‐diketone precursors is crucial for achieving optimal stereoinduction in this transformation. The resulting highly enantioenriched aminosulfonium ylides allow for further stereospecific elaborations to furnish aminosulfonium ylide oxides and sulfinamide. This work expands the boundaries of chiral sulfonium ylide chemistry, providing access to a broad range of previously elusive S‐stereogenic aminosulfonium ylide scaffolds. [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 applications. The authors propose a simple and efficient procedure using readily available materials and a copper catalyst. They successfully synthesized a variety of oxazoles with different functional groups. The method is versatile and can be used for late-stage installation of oxazoles into drug molecules and the synthesis of chiral ligands. The authors also suggest further exploration in carbene chemistry based on the mechanism proposed for the reaction. [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]