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trans-Ge/B 1,1-Hydroboration of Alkynylgermanes with 9-BBN
Zi-Long An - ,
Chao Chen - ,
Ao-Xiang Yu - ,
Dun-Xu Cao - ,
Yuan-Ye Jiang *- , and
Bin Xiao *
A 1,1-hydroboration of alkynylgermanes with unique trans-Ge/B stereochemistry under transition-metal-free conditions is reported. Mechanistic studies suggest that a pathway involving α-boration followed by a stepwise 1,2-Ge/H shift on the intermediate structurally lies between an alkyne–Ge+ π complex and a typical vinyl cation. The resulting Ge/B bimetallic modules, along with a Ge*/Ge/B trimetallic variant, can be conveniently transformed into trisubstituted olefins through iterative divergent cross-coupling. This work demonstrates that incorporating metalloids into classical organic reactions may offer unconventional chemical selectivity and efficient synthetic applications.

Organocatalytic Atroposelective Cross-Coupling of 2-Naphthols with Diaryliodonium Salts
Sushree Ranjan Sahoo - and
Vinod K. Singh *
Due to their modularity and conciseness, atroposelective cross-coupling is one of the most attractive approaches for synthesizing axially chiral binaphthyl molecules. While transition metal-catalyzed cross-couplings provide reliable synthetic strategies, alternative methods that accommodate a broader range of substrates without their pre-functionalization are highly beneficial. Here, we demonstrate that using the bifunctional organocatalyst (DHQD)2PHAL enables atroposelective cross-coupling of 2-naphthols and diaryliodonium salts with high efficiency, and yields (up to 72%) and excellent enantioselectivity (up to >99% enantiomeric excess). Further transformations of the products highlight the versatility of other binaphthyl compounds while maintaining their axial chirality.

Microwave-Assisted One-Pot Synthesis of Diverse Tribenzo[a,f,h]azulen-10-ones
Pradip S. Waghmare - ,
Anil Balajirao Dapkekar - , and
Gedu Satyanarayana *
Azulene-type polycyclic hydrocarbons have recently attracted a great deal of attention from researchers; however, their structure–property correlations and possible uses are not being fully explored due to the lack of effective synthesis techniques. Herein, we report a hitherto unexplored one-pot, microwave-assisted synthetic strategy toward diverse tribenzo[a,f,h]azulen-10-ones by tandem Suzuki coupling and a subsequent cyclo-condensation process. The strategy provides tribenzo[a,f,h]azulen-10-ones in good to excellent yields with structural versatility, including thiophene-embedded tribenzo[a,f,h]azulen-10-ones. In addition, UV–visible absorption studies have been used to investigate their structural and photophysical properties. This strategy offers a new platform for promptly synthesizing numerous unexplored azulenone units.

Metal-Free Visible-Light Excitation of TMSN3 Enables [3 + 2] Cycloaddition of Arylidenecyclopropanes with Olefins
Ya-Yu Wang - ,
Ting-Feng Fu - ,
Xiao Hu - ,
Bo Liu - ,
Ming-Yu Teng - ,
Guo-Li Huang *- , and
Lei Zhang *
A visible-light photoredox [3 + 2] cycloaddition reaction of arylidenecyclopropanes with olefins was developed, employing the readily available and commercially accessible TMSN3 as an efficient radical mediator. This method provides a convenient and efficient route to arylidenecyclopentanes from readily available starting materials, is metal-free, and features enhanced atom and step economy, excellent selectivity, extensive substrate versatility, favorable functional group compatibility, structural diversity, and mild reaction conditions, which further enable late-stage diversification. DFT calculations elucidated that this transformation entails sequential radical generation, radical addition, ring-opening, radical cyclization, and elimination steps.

Exploring the Skeletal Rearrangement/Self-Ring-Opening Reaction of Dibenzo[b,f][1,5]diphosphacines
Shuangchen Lv - ,
Haiyang Huang *- , and
Hongli Bao *
This study reports the first self-ring-opening reaction of a novel eight-membered heterocyclic skeleton, dibenzo[b,f][1,5]diphosphacyclooctatetraene (PCOT), into (Z)-alkenyldiphosphines, which involves the sequential cleavage of two phosphonium–ylide bonds and the formation of a C═C bond. Theoretical analyses further rationalize the stereoselective formation of Z-form products and the chemical driving force behind the phosphonium–ylide (P1═C1) bond cleavage. This work represents the first example of π-conjugated eight-membered phosphacycles featuring two internal phosphonium–ylide bonds and their self-ring-opening rearrangement.

Aryne Alder-Ene Reaction Enables Arylation of Conformationally Locked Styrenes
Tamal Ballav - ,
Srinath Barman - , and
Venkataraman Ganesh *
We report a transition metal-free aryne Alder-ene (AAE) reaction of conformationally locked styrenes like methylene indane (5,6-fusion) and methylene tetralin (6,6-fusion) to provide aryl-decorated indenes and dihydronaphthalenes. DFT studies compared the transition states between 5,6- and 6,6-fused systems. The synthetic utility of the 5,6- and 6,6-fused products was demonstrated.

eFluorination for the Rapid Synthesis of Fluorothioformates from Oxalic Acid Monothioesters
Feba Pulikkottil - ,
Marco Galzignato - ,
Jérémy Saiter - ,
Charles A. I. Goodall - ,
Bini Claringbold - , and
Kevin Lam *
An efficient and practical electrochemical method for synthesizing fluorothioformate derivatives, an underexplored functional group, is reported. The strategy is based on the anodic decarboxylation of oxalic acid monothioesters, which rapidly generates highly reactive alkyl (oxomethylidene)sulfonium intermediates. These intermediates are effectively trapped by the inexpensive and commercially available triethylamine trihydrofluoride (Et3N·3HF), which acts as both a nucleophilic fluoride source and a supporting electrolyte, leading to the formation of the desired fluorothioformates. This methodology enables the rapid and scalable synthesis of fluorothioformate derivatives, enabling their broader exploration in organic chemistry. In particular, these compounds can be readily and selectively converted to S-thiocarbamates and urea derivatives in a one-pot process through reactions with amines, demonstrating their synthetic utility. The scalability of this electrochemical fluorination was validated, showing no loss of yield. Cyclic voltammetry studies were carried out to shed some light on the mechanism of these novel transformations.

Synthesis of Inherently Chiral Germepins via Rh-Catalyzed Enantioselective C–H Germylation
Cheng-Gang Qian - ,
Hong Yan - ,
Jing-Yu Li - ,
Zi-Shuo Zhang - ,
Zi-Long An - , and
Bin Xiao *
A rhodium-catalyzed enantioselective C–H germylation reaction was developed, enabling the synthesis of germepin derivatives with diverse substitutions. This study represents a rare application of E–H/C–H (E = Si or Ge) dehydrogenation coupling reactions in synthesizing inherently chiral molecules, marking the first successful enantioselective synthesis of inherently chiral seven-membered heterocycles containing group 14 elements. Compared to their structurally analogous tribenzosilepins, tribenzogermepins exhibit enhanced stereochemical stability under the reaction conditions. Furthermore, the compatibility of the Si–H bond under identical conditions highlights the distinct reactivity of Si–H and Ge–H bonds.

Electrochemical Deoxyarylation of Aromatic Aldehydes and Ketones
Fengze Yao - ,
Yuan Gao - ,
Yachun Wang - ,
Li Zeng - ,
Aiwen Lei - , and
Wu Li *
Carbonyl-containing compounds serve as essential building blocks in various synthetic processes. However, due to the high bond energy of the C═O double bond, the traditional deoxygenation methods often require harsh conditions or toxic reagents. Direct carbonyl deoxygenative coupling of aldehydes and ketones is still challenging under mild conditions. Herein we report the successful establishment of an electroreductive coupling strategy utilizing aromatic carbonyls and terephthalonitrile. A key component of our approach is the use of closo-boranes, specifically (Et4N)2B10H10, which serve as an in situ deoxidant by single-electron oxidation.

Rh-Catalyzed Coupling of Cyclic 1,3-Dicarbonyl-Derived Iodonium Ylides with Cyclopropanols
Zongye Wang - ,
Mingxuan Liang - ,
Dongyang Zhang - ,
Wenteng Cai - ,
Zequan Xiang - ,
Mingtao Feng - ,
Miaolin Ke - , and
Shaoyu Mai *
Herein, we report a modular α-monoalkylation of cyclic 1,3-dicarbonyls with cyclopropyl alcohols through a cyclic iodonium ylide strategy. This approach is general, base-free, operationally simple, and suitable for various medically important (hetero)cyclic 1,3-dicarbonyls. A wide range of cyclopropyl alcohols, easily prepared from feedstock chemicals, can serve as modular and complement alkylating agents. Importantly, the newly formed carbonyl groups in the resulting products provide a versatile platform for numerous synthetic applications.

Synthesis of Dithioester Derivatives by Base-Mediated Fragmentation of 1,3-Dithiolanes
Hasan Pelit - ,
Mehmet Aytug Sinmaz - ,
Oyku Acelya Ildem - ,
Zeynep Mert - ,
Yigit Efe Turhan - ,
Elif Aydin - ,
Senem Dila Yilmaz - ,
Andrea Mentese - , and
Baris Yucel *
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Dithioesters are important agents for chain transfer in polymer chemistry and precursors in the synthesis of heterocycles. Straightforward approaches to their synthesis are therefore in demand. Outlined herein is a method to access such compounds in one-pot. 2-Aryl-1,3-dithiolanes undergo ring fragmentation with LiHMDS in CPME to generate aryl-dithiocarboxylates in 5 min at 100 °C. These anions are subsequently captured in the second step by addition of various alkyl halides and diaryliodonium salts to furnish a large library of dithioesters in good yields. The method can be also employed in a one-pot, one-step manner for alkyl bromides and allows the synthesis of dithioesters in gram scale.

Palladium-Catalyzed Hiyama Cross-Coupling of Heterocyclic Phosphonium Salts with Arylsilanes
Ya-Qi Liu - ,
Rui Yang - ,
Hongfang Li - ,
Teck-Peng Loh *- , and
Ming-Zhu Lu *
We report herein the palladium-catalyzed Hiyama cross-coupling of heterocyclic phosphonium salts with diverse (hetero)arylsilanes through C–P bond cleavage, providing an alternative approach for the highly regioselective functionalization of pyridines and relevant nitrogen-containing heterocycles. This silicon-based protocol is amenable to gram-scale synthesis and also applicable to the late-stage functionalization of pharmaceutically relevant complex molecules.

Metal-Free Catalytic N-Methylation of NH-Sulfoximines Using CO2
Subir Maji - ,
Mandira Saha - ,
Satyaki Sinha - ,
Priyankar Majumder - , and
Swadhin K. Mandal *
This study reports the catalytic N-methylation of NH-sulfoximines using carbon dioxide (CO2) under metal-free conditions. A mesoionic N-heterocyclic olefin (mNHO) was used as a catalyst for the N-methylation of NH-sulfoximines in the presence of 9-borabicyclo[3.3.1]nonane (9-BBN) under mild conditions. This process was used to convert various NH-sulfoximines into N-methylsulfoximines. This protocol was also applicable for the synthesis of 13C-labeled N-methylsulfoximines using 13CO2. A mechanistic cycle was proposed by performing a series of control reactions and successfully characterizing active catalytic intermediates by either single-crystal X-ray or NMR spectroscopic studies.

Synthesis of γ-Iodo-allylic Diboronic Esters via Atom Transfer Radical Addition of (Diborylmethyl)iodide to Alkynes
Kun Zhang - ,
Junling Zhang - ,
Qinqi He - ,
Jiefeng Hu *- , and
Su Jing *
Herein, we disclose a manganese-catalyzed approach that enables the direct iododiborylcarbofunctionalization of alkynes with a (diboronmethyl)iodide under mild conditions. This approach grants access to a range of structurally unique and synthetically useful γ-iodine-substituted gem-bis(boronate)s, which have hitherto been inaccessible. This atom-economical strategy displays excellent functional-group tolerance, encompasses a wide range of applicable substrates, and demonstrates a high Z:E selectivity (up to 96:4).

Installation of Site-Specific Inorganic and Organic Phosphate to Peptides and Proteins via Vinylaryl Sulfonium Reagents
Qingyun Yang - ,
Kun Zou - , and
Mingxuan Wu *
Protein phosphorylation is a very important post-translational modification that regulates diverse cellular activities. In addition to classic monophosphorylation, there is also oligophosphorylation from pyrophosphorylation to polyphosphorylation. Moreover, organophosphates may modify residues such as via AMPylation and ADPylation. Although plenty of new types of protein phosphorylation have been revealed, molecular mechanisms of the biological functions are still challenging to study due to the lack of a good method to prepare proteins of interest with such site-specific PTMs. Here we report a facile method to install inorganic and organic phosphates on peptides and proteins. Vinylaryl sulfonium with an electron-withdrawing group was applied to cysteine alkylation and subsequent cyclization by γ-sulfur yielding episulfonium. This highly electrophilic intermediate was later attacked by a phosphate reagent to yield site-specifically phosphorylated cysteine peptides and proteins. As a result, this method does not require a special precursor residue on peptides/proteins or activation of phosphate reagents. In addition, this method is applicable to diverse inorganic phosphates and organophosphate. Therefore, we believe that this method will accelerate protein phosphorylation research by simple preparation of site-specific modified proteins. We also believe it offers a simple bioconjugation strategy via a phosphate linker.

Electrochemical Strategy for the Radical Fluoroacetylation of Sulfoximines from Fluorinated Alkyl Carboxylic Acids
Xiaoman Li - ,
Jiawei Huang - ,
Huanhuan Song - ,
Liang Xu - ,
Jichang Liu *- ,
Mingyou Hu *- , and
Yu Wei *
The integration of trifluoroacetyl (CF3CO) groups into organic skeletons is a key research topic in synthetic chemistry given their significant potential to boost biological activity. Despite recent developments of strategies for incorporating trifluoroacetyl moiety via trifluoroacetyl radical intermediates, the practical utilization of inexpensive and readily available trifluoroacetic acids as trifluoroacetyl radical sources has not yet been developed. Herein, an electrochemical strategy has been employed to achieve the radical deoxygenative transformation of trifluoroacetic acids directly with the assistance of PPh3. The obtained trifluoroacetyl radicals are then coupled with sulfoximine species, thus enabling the synthesis of N-trifluoroacetylated sulfoximines. Additionally, other fluorinated alkyl carboxylic acids, including perfluoro-, difluoro-, and trifluoromethylcarboxylic acids, can also be efficiently utilized under these conditions, leading to their corresponding acylated sulfoximines. Moreover, the trifluoroacetylation of drug-based molecules and the easy execution of scale-up experiments highlight the applicability of this protocol.

Electronically Mismatched α-Addition of Electron-Deficient Alkenes via Photoinduced Polarity Transduction
Yuan-Yuan He - ,
Ze-Kun Yang - ,
Taro Matsuyama - ,
Yi Wei *- ,
Lan Qin - ,
Zhihan Zhang *- ,
Masanobu Uchiyama *- , and
Xiao-Qiang Hu *
Conjugate addition reactions are among the most important transformations in organic synthesis. Electron matching requirements normally restrict the site-selective β-addition of nucleophiles to conjugate acceptors, while regio-reversed α-additions have remained largely elusive. Here we describe a photoinduced polarity transduction strategy that overcomes electronic and steric limitations and enables the exclusively umpolung α-addition of diverse nitrogen nucleophiles to electron-deficient and -neutral alkenes under mild and base-free conditions. This reaction has broad functional group compatibility, shows excellent regioselectivity, and enables late-stage skeletal modification, promising considerable synthetic value. Experimental studies point to a photoinduced through-bond intramolecular charge-transfer (ICT) pathway.

Photoredox-Catalyzed Direct C(sp2)–H Difluoromethylation of Hydrazones with Difluoromethyltriphenylphosphonium Salt via Aminyl Radical/Polar Crossover
Xiao-Di Wu - ,
Li Wang - ,
Ji-Yu Tao - ,
Zhen-Yu Liu - ,
Zeng Liu - ,
Cheng Gao - ,
Dong-Ping Shen - ,
Yu Zhang - ,
Li-Li Zhao - , and
Kai Zhao *
This study describes an efficacious and generally applicable synthetic strategy for the incorporation of biologically and physiologically prominent difluoromethyl entity into synthetically crucial hydrazone scaffolds with bench-stable and easily accessible difluoromethyltriphenylphosphonium bromide. The broad substrate scope, excellent functional group compatibility, feasibility of step and atom economical one-pot synthetic manipulation, and environmentally benign and mild reaction conditions rendered this methodology an efficient tool for the preparation of synthetically and pharmaceutically prominent fluorine-containing imino compounds.

Stereoselective Nickel-Catalyzed Iterative 1,2-Reduction of Trisubstituted Enones to Cycloalkanols Bearing Two Contiguous Stereocenters
Yue Liu - ,
Chaoxin Yang - ,
Linhong Zuo - ,
Qixing Liu - ,
Xumu Zhang - ,
Cheng Hou *- ,
Congcong Yin *- , and
Haifeng Zhou *
Herein we first report a nickel-catalyzed asymmetric iterative 1,2-reduction of trisubstituted enones to cycloalkanols with two contiguous stereocenters in high yields with excellent diastereo- and enantioselectivities (36 examples, up to 98.5:1.5 er, >20:1 dr, TON = 500). The combined experimental and computational mechanistic studies suggested energy changes during two consecutive reduction processes and provided a range of unique mechanistic rationales that have not been disclosed in nickel-catalyzed asymmetric hydrogenation-related studies.

Enantioselective Conjugate Addition of Aldehydes to Oxetane- and Azetidine-Containing Nitroolefins: An Entry to Spirocyclic Pyrrolidines
Alena Budinská - ,
Quentin Lefebvre - , and
Helma Wennemers *
Enantioselective amine-catalyzed conjugate additions of aldehydes to oxetane- and azetidine-containing nitroolefins afford γ-nitroaldehydes as key building blocks en route to spirocyclic oxetane/azetidine-pyrrolidines. The study provided insights into the stability and reactivity of these β,β-disubstituted nitroolefins and enabled the enantioselective synthesis of chiral oxetanes and azetidines in moderate-to-high yields and enantioselectivities. This approach expands synthetic access to medicinally relevant scaffolds and broadens the scope of enantioselective organocatalytic transformations.

Concise Synthesis of Optically Active Cyclopropane β-Amino Acid Derivatives via Olefination of Cyclopropanone Surrogates
Myunggi Jung - and
Vincent N. G. Lindsay *
An expedient synthesis of cyclopropane β-amino acid derivatives is reported from readily accessible cyclopropanone surrogates. The addition of stabilized phosphorus ylides to 1-sulfonylcyclopropanols leads to the formation of highly electrophilic alkylidenecyclopropanes shown to be reactive in a telescopic aza-Michael reaction, in mild conditions. The transformation proceeds with complete diastereocontrol in favor of the trans products and is amenable to the rapid production of highly enantioenriched β-amino acid derivatives, peptidomimetics and spirocyclic analogues.

En Route to Anthanthrenes through Bottom-up APEX Strategy by peri-C–H Activation
Abhisek Metya - ,
Supreeta Sen - ,
Arya Bhattacharyya - , and
Modhu Sudan Maji *
Accessing PAHs having all zigzag edges remains elusive, and this work demonstrates a general synthetic strategy for the construction of one such scaffold, namely, anthanthrene, through Ru(II)-catalyzed APEX reaction at the masked-bay region. The protocol efficiently delivers a range of uniquely substituted anthanthrenes with excellent regioselectivity, which is supported by DFT studies. The synthesis of anthanthrone derivatives, a core structure of vat orange dyes, is another highlight of this study.

Diastereoselective Synthesis of Boryl-Substituted Vinylcyclopropanes via Deborylative Cyclization of Geminal Diboron Compounds
Heng-Yu Gu - ,
Xin-Yi Chen - ,
Yi-Fei Yang - , and
Kai Hong *
Herein we report a diastereoselective synthesis of boryl-substituted vinylcyclopropanes, a class of highly valuable synthetic building blocks, via deborylative cyclization of geminal diboron compounds. The method exhibits broad functional group tolerance and accommodates diverse alkyl and aryl α-substituents. The diastereoselectivity is primarily governed by the α-substituent (alkyl vs aryl), while olefin geometry in the side chain has a secondary influence. Mechanistic studies indicated distinct pathways: a concerted process for alkyl substrates and a carbanion intermediate for aryl derivatives. Synthetic utility of the products was also demonstrated.

One-Pot Stereoselective Synthesis of C-Glycosyl Amino Acids with Vicinal Stereocenters
Zhentao Zhang - ,
Jinhui Xie - ,
Jingrui Wang - ,
Yifeng Zhu - ,
Xinyu Gao - ,
Linxuan Li - ,
Nengzhong Wang *- ,
Nianyu Huang *- , and
Hui Yao *
A palladium-catalyzed cascade coupling between glycals and racemic α-nitroesters enables the stereoselective construction of C-glycosyl amino acids bearing two contiguous stereocenters, achieving dual stereocontrol (exclusive β-C1, up to 10:1 diastereomeric ratio at C7). This one-pot protocol at room temperature accommodates diverse substrates (25 examples). Mechanistic studies demonstrate that decarboxylation-induced C4-oxyanion directs 1,4-syn selectivity, while steric modulation governs C7 stereochemistry. Synthetic versatility is evidenced by gram-scale synthesis and late-stage functionalization to trihydroxy C-glycosides, 2,3-dideoxy sugars, and 4-O-amino acid conjugates.

Visible Light-Promoted Three-Component Reaction for the Synthesis of Pyrrolopyrazoles
Han-Peng Pan - ,
Shao-Shuai Chen - ,
Han Yang - ,
Ze-Yu Su - ,
Ya-Jie Chen - ,
Mao-Bi Zhu *- ,
Ai-Jun Ma *- , and
Xiang-Zhi Zhang *
A visible light-enabled three-component cascade assembles pyrrolopyrazoles from arylalkynes, benzoquinones, and 5-aminopyrazole through a mechanistically validated carbonyl–alkyne metathesis/(3 + 2)-cycloaddition/1,2-aryl migration sequence. This protocol delivers pyrrolopyrazole heterocycles in up to 96% yield with excellent functional group tolerance. Preliminary biological screening identified promising antitumor activity in selected products, highlighting the potential value of this method. The proposed reaction mechanism is supported by control experiments.

Palladium-Catalyzed Regioselective [3 + 2] Annulation with N-Allenamides at the Proximal C═C Bond: Synthesis of γ-Amino-α′-methylenecyclopentenones
Yidong Wang *- ,
Hang Zhou - ,
Yan Sun - ,
Shenglong Wang - ,
Ruiqiang Lu - ,
Shiwan Sun - ,
Ying Han - ,
Liuzhou Gao *- , and
Junliang Zhang *
A palladium-catalyzed [3 + 2] cycloaddition of cyclopropenones with N-allenamides has been developed. This methodology facilitates the synthesis of γ-amino-α′-methylenecyclopentenones in moderate to excellent yields with good regioselectivity and compatibility with various functional groups. The employment of N-allenamides as versatile 2C synthons enables simultaneous incorporation of both a nitrogen atom and a methylene group into cyclopentenones. Furthermore, this approach exhibits reverse regioselectivity when compared to general allenes. Density functional theory calculations successfully elucidated the origin of the observed regioselectivity.

Ether-Directed Enantioselective C(sp2)–H Borylation for the Synthesis of Axially Chiral Biaryls
Changji Liu - ,
Chengcai Xia - ,
Shu-Yong Song *- , and
Senmiao Xu *
We report an ether-directed enantioselective C(sp2)–H borylation catalyzed by a chiral bidentate boryl ligand (CBL)/iridium system for constructing axially chiral biaryls. This method delivered diverse chiral biaryls with good to high enantioselectivities, accommodating varied electronic and steric substituents on the aryl rings. Gram-scale synthesis and downstream transformations of the C–B bond underscored its practicality.

Hydrogen-Bond-Mediated Glycosylation Reactions with Glycosyl Picolinates
Mohan Lal - ,
Himanshu Gangwar - ,
Anand Gaurav - ,
Ariza Khanam - ,
Ashwani Tiwari - , and
Pintu Kumar Mandal *
Herein, we report a generally applicable hydrogen-bond-mediated glycosylation protocol of glycosyl picolinate donors with a charged (thio)urea hydrogen-bond-donor catalyst. A variety of nucleophiles, including complex natural products, glycosides, amino acids, and less nucleophilic phenolic acceptors were also glycosylated successfully. Hydrogen-bond-mediated glycosylation systems combined with different strategies were also explored to achieve stereoselective glycosylation. A mechanistic study revealed that catalysts form the donor-catalyst noncovalent complex through hydrogen bonds and then produce the oxocarbenium species.

Divergent Construction of Spirocyclopentene-3,2′-indolines with Vicinal Stereocenters via Palladium-Catalyzed Aza-Wacker Cyclization
Fan Yang - ,
Huai-Yu Bin - ,
Feng-Kai Zhao - ,
Li Cheng - ,
Hao Wang *- , and
Jian-Hua Xie *
Herein, we report an aerobic palladium-catalyzed aza-Wacker cyclization to produce spirocyclopentene-3,2′-indolines with vicinal stereocenters. Using 1,2-bis(diphenylphosphino)benzene (dppbz) and pyridine as ligands, we achieved a ligand-modulated diastereodivergent synthesis, producing cis- and trans-spirocyclopentene-3,2′-indolines with exceptional yields and diastereoselectivities. Density functional theory (DFT) calculations revealed that selective aza-Wacker cyclization proceeds through distinct trans- and cis-aminopalladation mechanisms.

Enantio- and Diastereoselective Synthesis of P-Stereogenic Phospholane Oxides via Cobalt-Catalyzed Hydroalkylation
Dao-Yong Zhu *- ,
Ya-Ting Zhang - ,
Fu Cheng - ,
Qiao Kong - ,
He-Xiang Dang - ,
Hai-Juan Jiao - ,
Ye Zhang - ,
Xiao-Ming Zhang - ,
Shao-Hua Wang *- , and
Si-Yao Li
Chiral phospholane ligands and catalysts have been widely applied in asymmetric catalysis and synthesis. However, the construction of the chiral phospholane skeleton remains challenging and primarily relies on the use of chiral auxiliaries or resolution. In this work, a highly enantioselective and diastereoselective synthesis of P-stereogenic phospholane oxides has been achieved through a cobalt-catalyzed desymmetric hydroalkylation strategy. This method enables the construction of two discrete stereocenters with excellent yields and enantiomeric excesses.

A Mechanistic Perspective on Photocatalytic EnT-Enabled C3-N-Heteroarylation of Aryl Quinoxaline via C(sp2)–C(sp2) Coupling
Raju Mandal - ,
Subhendu Ghosh - ,
Swastik Laha - ,
Pritishree Panigrahi - ,
Kalishankar Bhattacharyya *- , and
Bhisma K. Patel *
An EnT-mediated C3-N-heteroarylation of 2-aryl quinoxalines via decarboxylative radical–radical cross-coupling (C(sp2)–C(sp2)) with oxime esters is presented. Upon photoactivation, the triplet energy of the photocatalyst is transferred to both reacting partners (oxime ester and 2-phenylquinoxaline). The excited oxime ester undergoes decarboxylative fragmentation to a C-centered N-heteroaryl radical and an N-centered imine radical. The former attacks the C3 site of the quinoxaline diradical, while the latter acts as a hydrogen atom abstractor (HAA). Computational studies revealed that C–C bond formation with the heteroaryl radical is energetically more favorable than C–N bond formation.

Development and Mechanistic Insights into Nef Reaction for Preparation of Aldehydes Using Singlet Oxygen
Ira Novita Sari - ,
Bobo Yan - ,
Tatsuya Morozumi - ,
Yuichi Kamiya - , and
Taiki Umezawa *
The Nef reaction for conversion of nitro compounds to aldehydes is described. Various functional groups, such as ethers, silyl ethers, acetals or esters, were tolerated to give aldehydes in high yields using Cs2CO3 and singlet oxygen as an oxidant. Transformations of nitromethyl groups into hydroxymethyl groups were achieved in a one-pot operation. The mechanism involved in the Nef reaction was studied using ion chromatography and radical scavengers, which resulted in the proposal of two unique reaction pathways.

Hexadehydro Diels–Alder/Alkynyliodanation Cascade: A Highly Regioselective Entry to Polycyclic Aromatics
Shunya Morohashi - ,
Liejin Zhou - ,
Kazuya Kanemoto *- ,
Eunsang Kwon - , and
Naohiko Yoshikai *
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We report here a cascade process integrating the hexadehydro Diels–Alder (HDDA) reaction with alkynyliodanation, enabling efficient synthesis of highly substituted aryl-λ3-iodanes. Heating a mixture of a tetrayne and an alkynylbenziodoxole induces regioselective insertion of the tetrayne-derived aryne into the alkynyl–iodine(III) bond, yielding a 1,4-dialkynyl-2-iodanyl-3-aryl(or alkyl)benzene derivative. The unique regiochemistry facilitates subsequent π-extension, allowing divergent access to polyaromatic frameworks, such as helicenes and cyclopenta[cd]pyrenes, underscoring the utility of aryne carboiodanation in complex aromatic synthesis.

Copper-Catalyzed Reductive Hydroamination of Inactive Diarylacetylenes with Nitroarenes
Zhiyou Li - ,
Jie Tang - ,
Xinyue Ma - ,
Long Liu *- ,
Mengjie Cen - ,
Qiang Li - ,
Tianzeng Huang - ,
Chunya Li - , and
Tieqiao Chen *
Reductive hydroamination of stable and readily available nitroarenes with unsaturated hydrocarbons represents practical access to amines. Herein, we report a simple Cu-catalyzed amine synthesis via the reductive hydroamination of nitroarenes with inactive diarylacetylenes. A series of diarylacetylenes are successfully transformed into secondary amines under mild conditions with good functional group tolerance.

Monobromination of Cubane 1,4-Diester, A Synthetic Handle for Fluorosulfonylation and Giese-Type Reactions
Laly Donnier-Valentin - ,
Julien Legros - ,
Catherine Fressigné - ,
Daniela Vuluga - ,
Bruno Linclau - , and
Michaël De Paolis *
The bromination of cubane 1,4-diester is described for the first time. The versatility of the C–Br bond for forging C–S and C–C bonds was demonstrated. The fluorosulfonylation reaction allowed the first entry of the cubane in click chemistry illustrated with nucleophiles, electrophiles, and alkynes. The grafting of appendages was illustrated with amino acids and dipeptides, enabling the discrimination of the diesters via cyclization into “fused cubane-lactam” structures.

Pd(II)-Catalyzed Annulation of Alkynes with 4-Hydroxy-3-Maleimidecoumarin: One-Pot Construction of Multiple Rings
Kumud Sharma - ,
Abhilash Sharma - ,
Kashmiri Neog - ,
Nasib Kayastha - ,
Babulal Das - , and
Pranjal Gogoi *
A Pd(II)-catalyzed cascade annulation of 4-hydroxy-3-maleimidecoumarin with alkynes has been demonstrated. This unique strategy highlights an interesting process for the cascade formation of three rings (three-, five-, and six-membered) of carbocycles and heterocycles through spiro-annulation followed by cyclization. This strategy offers an attractive platform for synthesizing various coumarin-fused complex structures in good yields. Additionally, six synthesized compounds have been unambiguously confirmed by single-crystal X-ray diffraction analysis.

Base Promoted Hydrogenation of N-Heteroarenes with Ammonia Borane and DMSO
Doudou Jia - ,
Zhituan Ai - ,
Xinya Yuan - ,
Guangbin Zhou - ,
Guodong Zhang - ,
Pan Gao - , and
Feng Chen *
Herein, we report a sodium tert-butoxide-promoted reduction of N-heteroarenes using ammonia borane and dimethyl sulfoxide (DMSO) under mild reaction conditions. This method demonstrates broad functional group compatibility across diverse N-heteroarene substrates. Notably, substituting DMSO with deuterated DMSO-d6 enables the synthesis of C3-deuterated 1,2,3,4-tetrahydroquinolines with remarkable positional selectivity. Mechanistic investigations indicate that the protons are derived from both ammonia borane and DMSO. This strategy establishes a novel and environmentally benign approach for the synthesis of (deuterated) N-heterocycles, offering practical advantages in terms of operational simplicity and sustainable reaction conditions.

A Tricyclo[4.3.1]decane Diterpenoid Skeleton from Croton laui: Isolation and 1H NMR-Based Metabolomic Profiling
Qing Li - ,
Chen-Sen Xu - ,
Hao-Lin Yu - ,
Yu Zhang - ,
Jin Wang - ,
Yi-Bo Shen - ,
Hong-Wei Wu - ,
Min-Min Gu - , and
Zhi-Xin Liao *
Lauicyclone A (1), a new skeletal diterpenoid characterized by an unprecedented carbon skeleton, represents the first reported natural product featuring a complex tricyclo[4.3.1]decane framework. Along with Lauicyclones B–E (2–5), all five compounds were isolated from Croton laui. Comprehensive spectroscopic analyses, quantum-chemical calculations, and X-ray diffractions were used to identify their structures. The antitumor mechanism of compound 1 was investigated using 1H NMR-based metabolomics.

Asymmetric Synthesis of 10-Demethoxyvincorine Enabled by Dual Ni/Ti-Catalyzed Reductive Cyclization
Yanxia Zhen - ,
Wei Jiang - ,
Yuanzhen Xu - ,
Xiangyu Hui - ,
Xiaoran Shi - ,
Huanhuan Zou - ,
Qianhu Chen - ,
Junhan Chen - ,
Hongbo Wei *- , and
Weiqing Xie *
Herein, we report the asymmetric synthesis of 10-demethoxyvincorine in 12 steps. The synthesis is highlighted by several key transformations: (1) a Pd-catalyzed Catellani-type reaction for the preparation of C2-alkylated tryptamine, (2) a chiral phosphoric acid (CPA)-catalyzed asymmetric bromocyclization to construct enantioenriched 3a-bromo-hexahydropyrroloindoline, (3) a dual Ni/Ti-catalyzed reductive cyclization to establish the bridged ring system, and (4) a SmI2-promoted reductive cyclization to forge the strained E-ring.

Translation of Nickel-Catalyzed C(sp2)–C(sp3) Cross-Electrophile Coupling to Non-Amide Solvents
Brett D. Akana-Schneider - ,
Julianna M. Mouat - ,
Sisi Zhang - ,
Michelle E. Akana - ,
Bin Wu *- , and
Daniel J. Weix *
The cross-electrophile coupling of organobromides is widely utilized in organic synthesis but generally requires undesirable amide solvents (e.g., DMF, DMA, and NMP). We report that the combination of a strongly donating, bidentate nitrogen ligand, LiI, and 4-picoline enables coupling in a variety of alcohol, ester, and ethereal solvents at up to 50 g scale. An improved synthesis of the optimal ligand, 4,4′-bis(dimethylamino)-2,2′-bipyridine, is also reported on the basis of the reductive homocoupling of 4-dimethylamino-2-chloropyridine.

Copper-Mediated Three-Component Reaction for the Synthesis of N-Sulfonylamidine on DNA
Tae Yeon Kwon - ,
Yeonhee Lee - ,
Kyung-Jin Cho - , and
Hyun Jin Kim *
DNA-encoded library (DEL) technology is a transformative tool for identifying bioactive compounds in pharmaceutical research. This study presents an optimized copper-mediated reaction to synthesize N-sulfonylamidine derivatives from DNA-conjugated alkynes and sulfonyl azides under mild conditions. Amines serve as nucleophiles, enabling selective functionalization under mild conditions while preserving DNA integrity. Through systematic refinement of reaction conditions and substrate evaluation, the approach demonstrated a high tolerance to diverse functional groups, significantly expanding DEL-accessible chemical space. The developed DNA-compatible method underscores the role of DELs in enhancing drug discovery by facilitating the introduction of novel pharmacophores into compound libraries.

Kinetic Resolution to Simultaneously Access Both Primary and Secondary NH-Unprotected Chiral Amines via Ir-Catalyzed Asymmetric Reductive Amination
Junbin Shi - ,
Shaoxiong Wu - ,
Haizhou Huang - ,
Hanlei Qin - ,
Huiling Geng *- , and
Mingxin Chang *
This report describes a new kinetic resolution–asymmetric reductive amination strategy to collectively gain access to both primary and secondary chiral NH-unprotected amines. Catalyzed by the complex of iridium and bulky and tunable phosphoramidite ligands, various ketones and racemic primary amines could be smoothly converted to two different types of amine products. Bronsted acids as additives play triple roles, decreasing the inhibitory effect, promoting the formation of the imine intermediates, and guiding the reaction to proceed through “outer-sphere” H-addition along with the bulky ligand.

Visible Light-Promoted Defluorinative Alkylation of Trifluoromethyl Ketones with α-Aminoalkyl Boron Species
Yue Zhang - ,
Kun Li - ,
Zhihong Wang - ,
Liangfu Tang *- , and
Zhijin Fan *
In this study, we developed a photoredox-catalyzed defluorinative cross-coupling method for trifluoroketones and alkyl boronic acids. The reaction afforded a series of novel α,α-difluoroketone derivatives, and in vitro fungicidal activity revealed that some of these compounds exhibited moderate to excellent activity against Rhizoctonia solani and Botrytis cinerea. In particular, compound 3d showed an EC50 value of 4.27 μg/mL against B. cinerea and can be used as a fungicidal lead compound for further optimization.

Oxindole-Terminated Quinoidal Compounds with Ultrahigh Electron Affinity: Synthesis and Applications
Tianzuo Wang - ,
Kai Guo *- ,
YiBo Shi - ,
Chenhui Xu - ,
Jingjing Shi *- ,
Yunfeng Deng *- , and
Yanhou Geng
Six quinoidal compounds terminated by oxindole have been synthesized via selective nucleophilic addition, dehydroxylation, and oxidation. Through the modification of the quinoidal core and terminal benzene rings with fluoride atoms or cyano groups, the LUMO energy levels of the quinoidal compounds can be tuned within the range −4.05 to −4.54 eV. The quinoidal molecules exhibited electron transport behavior and can be used as dopants to dope an oligo(ethylene glycol)-substituted polythiophene.

Enantioselective and Regiodivergent Skeletal Transformations of 1,2,3-Thiadiazoles to Alkylidene Dihydrothiophenes
Cunzhi Chen - ,
Youwei Chen - ,
Hongguang Du - ,
Jiaxi Xu - , and
Zhanhui Yang *
By leveraging the Rh-catalyzed asymmetric skeletal editing of 1,2,3-thiadiazoles, we successfully achieve the ligand-controlled enantioselective and regiodivergent synthesis of structurally diverse 2- and 3-alkylidene 2,3-dihydrothiophenes. Late-stage structural editing of complex natural and drug molecules is also enabled.

Palladium Complex Grafted on PEG-Based Amphiphilic Polymers as ppm Level Micellar Catalysts for Suzuki–Miyaura Coupling in Water
Song Xiao - ,
Minghang Wang - ,
Yiming Liu - ,
Meiqi Li *- , and
Yong Jian Zhang *
A series of bisphosphine-grafted amphiphilic polymers based on polyethylene glycol-poly(vinylethylene glycol) (PEG–PVEG) copolymers have been synthesized by using allylic etherification polymerization as a pivotal step. Self-assembling of the palladium complexes of the obtained amphiphilic polymers into spherical micelles has been investigated by UV–vis, DLS and TEM analysis. The outstanding catalytic performance of the present micellar palladium catalyst has been evidenced in the aqueous Suzuki–Miyaura coupling reaction, achieving remarkable efficiency even at a low catalyst loading of 100 ppm within 2 h.

Stereoisomerism in Trimacrocyclic Structures Fused by a Pillar[6]arene and Two [8]Cycloparaphenylenes
Hanchi Zhong - ,
Kai Lan - ,
Jiao Ming - ,
Dongmei Zhang - , and
Chuyang Cheng *
Stereoisomerism in pillararenes, particularly chiral isomerism from atropisomers, has intrigued organic chemists. Herein, we report the synthesis and characterization of a trimacrocyclic system formed by fusing two [8]cycloparaphenylenes with a pillar[6]arene. This system exhibits unique stereoisomerism, yielding a racemic mixture and a meso compound. The isomers were characterized using NMR, HRMS, and single crystal X-ray diffraction. This study offers valuable insights into constructing chiral isomers in macrocycles and enriches our understanding of stereochemistry.

Copper-Catalyzed Reductive Alkylation of β-Acyl Allylic Thioethers with Alkyl Bromides to Access α-Branched Enones with Flexible Alkyl Chains
Qin-Qin Dang *- ,
Xu Tian - ,
Hui Li - ,
Xue-Ni Liu - , and
Zhen-Kang Wen *
Replacing alkyl organometallic reagents with alkyl bromides to achieve desulfurative alkylation of thioethers has been a long-standing challenge in desulfurative functionalization of organosulfur compounds. Herein, we report a copper-catalyzed reductive tertiary alkylation of β-acyl allylic sulfides with α-carbonyl alkyl bromides under mild reaction conditions. The reaction accommodates a broad substrate scope with good functional group compatibility, providing a direct route to install diversified (sp3)-carbon quaternary centers at the allylic position of α-branched enones. Further synthetic applications of this protocol have been demonstrated with scale-up experiments and late-stage modification of the products.

Synthesis of (+)- and (−)-Batzelladine C Based on a Cyclization/Carbonylation/Double Cyclization Cascade: Revision of the Absolute Configuration
Tianci Yue - ,
Taichi Kusakabe - ,
Kyoka Someya - ,
Takuya Tsukamoto - ,
Keisuke Takahashi - , and
Keisuke Kato *
Syntheses of guanidino alkaloids (+)- and (−)-batzelladine C are described. The key feature of the syntheses is the cyclization/carbonylation/double cyclization cascade of optically active propargyl guanidine. The tricyclic guanidino cores bearing three stereogenic centers and an ester functionality were constructed in a single step. The esters with a hydroxy group were then converted into (+)- and (−)-batzelladine C. The absolute configuration of natural (−)-batzelladine C was revised to the (11S,13R,15S) configuration.

Triarylmethyl Cations as Photocatalysts for Radical-Mediated Cycloaddition Reactions
Tomoya Hisada - ,
Kazumichi Maeda - ,
Yasuhiro Yamashita *- , and
Shu̅ Kobayashi *
We have developed a novel photocatalytic system using readily available triarylmethyl cations for radical-mediated (4 + 2) and (2 + 2) cycloaddition reactions. A variety of substituted triarylmethyl cations were investigated, and the optimal catalyst exhibited high efficiency and broad substrate scope, affording the desired cycloadducts in good to excellent yields with high regio- and diastereoselectivities. Furthermore, the catalyst could be immobilized on a polymer support and reused multiple times without a significant loss of activity.

Copper-Catalyzed Enantioselective (3 + 3) Cycloaddition of Ethynyl Methylene Cyclic Carbamates with N,N′-Cyclic Azomethine Imines
Ya-Hui Li - and
Xiang-Ping Hu *
A copper-catalyzed asymmetric cross 1,3-dipolar cycloaddition between 2-aminoallyl zwitterions generated in situ from ethynyl methylene cyclic carbamates and N,N′-cyclic azomethine imines has been realized. The reaction, which utilizes a commercially available chiral tridentate N-ligand, delivers a range of functionally rich chiral hexahydro-8H-pyrazolo[1,2-a][1,2,4]triazin-8-one derivatives in 51–99% yields with good to high enantioselectivities (44–95% ee).

Regio- and Diastereoselective Cascade Reactions of Bicyclo[1.1.0]butanes: Access to gem-Difluorinated Carbocyclic Rings
Zhiyi Zhang - ,
Hao Wu - ,
Wenjie Xu - , and
Dachang Bai *
gem-Difluorinated carbocyclic rings are attractive motifs in drug development. Herein, we report the transition-metal free cascade reaction of bicyclo[1.1.0]butanes (BCBs) with gem-difluorocyclopropenes for the synthesis of gem-difluorinated carbocyclic rings with excellent regio- and diastereoselectivity. This method was successfully applied to provide a broad range of gem-difluorinated cyclopentenes and cyclopropanes, which could undergo a variety of difluoromethylene (CF2) retaining transformations.

His126 Substitution Shifts Perakine Reductase Activity from Carbonyl Reduction to Ene Reduction
Nannan Tu - ,
Bin Liu - ,
Yun Zhou - ,
Junbo Gao - ,
Yan Zhang - ,
Xiangrui Jiang *- , and
Lianli Sun *
Perakine reductase (PR) is an aldo-keto reductase (AKR) carbonyl reductase. His126 is one of the AKR catalytic tetrads in PR. Substitution of His126 with any other amino acids except Gln switched PR to an ene reductase. Molecular simulation suggested that the substrate-binding pose and the properties of the 126 residue determined the chemoselectivity. Given the strict conservation of His126 in AKR superfamily carbonyl reductases, modification of the corresponding site is a feasible strategy to design AKR-derived novel ene reductases.

Palladium-Catalyzed Domino Heck/Decarboxylative Cyanomethylation of Indoles and Alkenes with Cyanoacetate Salts
Ping-Xin Zhou *- ,
Yang Liu - ,
Mengjuan Li - ,
Hang Chen - ,
Tao Wu - ,
Xinyang Chen - ,
Kaikai Wang - ,
Feng Ren *- ,
Yun Fu *- , and
Yong-Min Liang
A palladium-catalyzed reaction of indoles with cyanoacetate salts enables the synthesis of 2,6-disubstituted indolines via tandem dearomatization/decarboxylative cyanomethylation. Remarkably, this is the first example of indole difunctionalization at the C2 and C6 positions. Moreover, this methodology extends to the palladium-catalyzed cyclization/decarboxylative cyanomethylation of aryl halide-tethered alkenes.

Ligand-Controlled Preparation of Aryl-Substituted Allenes Enabled by Nickel-Catalyzed Reductive Coupling of Secondary Propargylic Carbonates with Aryl Halides
Ruotong Li - ,
Jie Hu - ,
Yonghao Xi - ,
Hegui Gong *- , and
Weichen Huang *
Herein, we developed a new method for the synthesis of aryl-substituted allenes through a nickel-catalyzed reductive coupling reaction between secondary propargyl carbonates and aryl halides. By employing the dimethyl-1,10-phenanthroline ligand, we achieved a ligand-controlled, regioselective nickel-catalyzed reductive arylation, overcoming the structural limitations of propargyl electrophiles. Notably, this reaction exhibits exceptional functional group compatibility, rendering it particularly suitable for late-stage allenylation modifications of complex molecules.

Design and Synthesis of Chiral Spiro Monophosphinites with a 3-Oxo-1,1′-spirobiindane Scaffold and Their Application in Rhodium-Catalyzed Asymmetric Hydrogenation of Dehydroamino Acid Esters
Zheng-Yan Huang - ,
Pei-Yu Hu - , and
Jian-Hua Xie *
A new class of chiral spiro monophosphinites, based on a unique non-C2-symmetric 3-oxo-1,1′-spirobiindane scaffold featuring a large dihedral angle, has been effectively designed and synthesized. From readily accessible resources, these chiral spiro monophosphinites were synthesized via eight steps in 16–32% yields. Their excellent performance in the rhodium-catalyzed asymmetric hydrogenation of β-dehydroamino acid esters underscores the critical impact of the large dihedral angle in enhancing the activity and enantioselectivity.

Azulene-Fused seco-Hexabenzocoronene-Based Nanographenes
Haifan Zhang - and
Peng An *
Due to the unique electronic structure, azulene-containing polycyclic aromatic hydrocarbons attract significant attention toward tuning the chemical and electronic properties of benzenoid carbocyclic systems. Here, we report the synthesis and properties of two types of azulene fused, seco-hexabenzocoronene-based nanographenes. The X-ray crystallographic analysis indicated their nonplanar structures with highly torsional periphery in the solid structures. The typical narrow highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) energy gaps, long-wavelength absorption, and anti-Kasha emissions were investigated by experimental and computational studies. Interestingly, these nanographenes exhibited a pronounced photothermal effect.
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