Chemistry - An Asian Journal, Год журнала: 2023, Номер 18(11)
Опубликована: Апрель 10, 2023
Dirhodium complexes bearing bulky carboxylate ligands are synthesized and characterized. The steric bulk of could affect the reaction selectivity in Rh-catalyzed intramolecular reactions: Rh catalysts with provided five-membered ring products preferentially via insertion into a carbon-hydrogen bond. Meanwhile, six-membered were obtained using conventional carbon-carbon double
Язык: Английский
Journal of the American Chemical Society, Год журнала: 2025, Номер unknown
Опубликована: Апрель 10, 2025
Herein, we disclose the discovery and development of a site-, regio-, diastereo-, enantioselective aryl C-H bond cyclopropylation using diazomethyl hypervalent iodine reagents, styrenes, paddlewheel dirhodium carboxylate catalysts. A key aspect this work was catalytic generation chiral Rh(II) carbene through an electrophilic aromatic substitution with carbynoids. The strategy allows construction cyclopropane rings bonds from feedstocks drug molecules promises to reach unexplored "cyclopropanated" chemical space highly difficult by current strategies.
Язык: Английский
Процитировано
0
Chinese Journal of Chemistry, Год журнала: 2025, Номер unknown
Опубликована: Июнь 3, 2025
Comprehensive Summary The chiral cyclopropane framework is a crucial structural motif in bioactive molecules such as pharmaceuticals and natural products. Asymmetric cyclopropanation of alkenes via transition metal‐catalyzed carbene transfer represents one the most direct approaches for synthesizing cyclopropanes. While significant progress has been made asymmetric α‐C‐substituted carbenes, highly enantioselective α‐silyl which possess greater transformation potential, remains largely unexplored. In this study, we report Cu(I)/chiral bisoxazoline catalytic system that enables cyclopropanation/Cope rearrangement reactions between α‐silyl‐α‐alkenyl carbenes (generated from ring opening 1‐silyl cyclopropene) alkenes. This methodology provides access to series cyclopropylsilanes containing stereogenic quaternary carbon centers well allylic silane moieties cycloheptadienylsilanes, thereby expanding diversity organosilicon compounds. Theoretical calculations reveal rate‐determining step involves cyclopropene, where silyl group not only dictates regioselectivity but also significantly influences stereoselectivity reaction through its steric rigid properties.
Язык: Английский
Процитировано
0
Advanced Science, Год журнала: 2024, Номер 11(18)
Опубликована: Март 2, 2024
Abstract The salinilactones, volatile marine natural products secreted from Salinispora arenicola , feature a unique [3.1.0]‐lactone ring system and cytotoxic activities through hitherto unknown mechanism. To find their molecular target, an activity‐based protein profiling with salinilactone‐derived probe is applied that disclosed the disulfide‐isomerases (PDIs) as dominant mammalian targets of thioredoxin (TRX1) secondary target. inhibition disulfide‐isomerase A1 (PDIA1) TRX1 confirmed by biochemical assays recombinant proteins, showing (1 S ,5 R )‐salinilactone B more potent than its )‐configured enantiomer. salinilactones bound covalently to C53 C397, catalytically active cysteines isoform PDIA1 according tandem mass spectrometry. Reactions model substrate demonstrated cyclopropyl group opened attack thiol at C6. Fluorophore labeling experiments showed cell permeability salinilactone‐BODIPY (dipyrrometheneboron difluoride) conjugate co‐localization PDIs in endoplasmic reticulum. study one first pinpoint target for microbial product, it demonstrates can achieve high selectivity despite small size intrinsic reactivity.
Язык: Английский
Процитировано
3
Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(44)
Опубликована: Сен. 12, 2023
Although 2-furyl-carbenes (furfurylidenes) are prone to instantaneous electrocyclic ring opening, chiral [BiRh]-paddlewheel complexes empowered by London dispersion allow (trifluoromethyl)furfurylidene metal be generated from a bench-stable triftosylhydrazone precursor. These reactive intermediates engage in asymmetric [2+1] cycloadditions and hence open entry into valuable trifluoromethylated cyclopropane or -cyclopropene derivatives optically active form, which important building blocks for medicinal chemistry but difficult make otherwise.
Язык: Английский
Процитировано
7
Advanced Synthesis & Catalysis, Год журнала: 2024, Номер 366(16), С. 3466 - 3473
Опубликована: Июнь 5, 2024
Abstract We are reporting the preparation and use in cross‐coupling reactions of a newly developed, bench‐stable (1‐fluorocyclopropyl)metalloid reagent. The Stille reaction described for this α‐fluorinated stannane reagent is amenable to wide range aryl alkenyl (pseudo)halides bearing variety functional groups. An enantioenriched cross‐coupled product was also obtained from corresponding 1‐fluorocyclopropyltin an ester handle. Finally, chemical stability 1‐fluorocyclopropyl moiety demonstrated by performing several post‐functionalizations.
Язык: Английский
Процитировано
2
Chemical Communications, Год журнала: 2024, Номер 60(57), С. 7327 - 7330
Опубликована: Янв. 1, 2024
Herein, we report the use of a molecular-defined rhodium( ii ) coordination polymer (Rh-CP) as heterogeneous, recyclable catalyst in carbene transfer reactions.
Язык: Английский
Процитировано
2
Chemistry - A European Journal, Год журнала: 2023, Номер 30(4)
Опубликована: Сен. 18, 2023
The tremendous importance of dirhodium paddlewheel complexes for asymmetric catalysis is largely the result an empirical optimization chiral ligand sphere about bimetallic core. It was only recently that a H(C)Rh triple resonance
Язык: Английский
Процитировано
5
Chemical Communications, Год журнала: 2022, Номер 58(60), С. 8416 - 8419
Опубликована: Янв. 1, 2022
Silylcyclopropenes are employed as precursors of α-silyl vinyl carbenes and trapped with alkenes. Cyclopropylsilanes were obtained in good yields ample scope complete regio- diastereoselectivity. Stereoretentive protodesilylations enabled access to cis-1,2-disubstituted cyclopropanes. Cyclopropylstannanes -germanes can also be prepared from the corresponding cyclopropenes.
Язык: Английский
Процитировано
8
Journal of the American Chemical Society, Год журнала: 2024, Номер unknown
Опубликована: Сен. 11, 2024
Carboxamidates as equatorial ligands in dirhodium paddlewheel catalysts are widely believed to increase selectivity at the expense of reactivity. The results combined experimental and computational approach described this paper show that one has beware such generalizations. First,
Язык: Английский
Процитировано
1
ChemistryEurope, Год журнала: 2024, Номер 2(6)
Опубликована: Окт. 10, 2024
Abstract The oxygenated sesquiterpenoid (‐)‐integrifolian‐1,5‐dione, which originates from a plant that finds widespread use in South American traditional medicine, is distinguished by rigid bicyclic framework consisting of cyclopropane cis ‐annulated to cyclodecane ring. first total synthesis this demanding target described, relies on highly selective cyclopropanation reaction an α‐stannylated‐α‐diazoester catalyzed heteroleptic dirhodium paddlewheel complex, followed unprecedented Stille‐type cross coupling the resulting stannylated with methyl iodide as electrophilic partner form all‐carbon quaternary stereocenter at one bridgehead positions. Equally decisive was bicyclization strategy based lactonization/ring expansion ultimately allowed strained ten‐membered carbocycle be forged.
Язык: Английский
Процитировано
1