Chemical Communications, Journal Year: 2024, Volume and Issue: unknown
Published: Dec. 10, 2024
We demonstrate the participation of cobalt in a photoinduced LMCT process, which leads to formation ligand-based radical species and enables both homo hetero cross-dehydrogenative coupling indoles with decent yield.
Language: Английский
Helvetica Chimica Acta, Journal Year: 2022, Volume and Issue: 105(12)
Published: Oct. 25, 2022
Abstract A hyperresponsive tool to assess supramolecular catalysis, the cyclization of di‐epoxides into cyclic ethers is used elucidate difference between pnictogen‐bonding and Lewis acid catalysis systematically. For all stereoisomers, most tested catalysts follow Baldwin rules. Brønsted anion–π afford almost only products. acids such as SbCl 3 , BF BiCl give poorest selectivity, with at least 50 % (B) products for stereoisomers. In clear contrast, optimized operating on Sb(III) Sb(V) level fused anti‐ (A) bicycles main product trans epoxides, independent syn or anti relation two epoxides. cis series, BA exclusively diastereomers, while diastereomers equal amounts AB show similarly special trends. These unique characteristics support that differs from can arguably be defined its non‐covalent counterpart, just like hydrogen‐bonding understood appreciated counterpart catalysis. Computational studies origin selectivity reveal an introvert deep σ hole surrounded by planar ring ligands. Central pnictogen‐bond attraction against peripheral steric repulsion then forces epoxide break open. transient antimony oxidation in intermediates accounts chemoselectivity catalysts. Presumably due insufficient accessibility their holes, activity tetrel‐bonding negligible. The division powerful irrelevant does not exist respective orthodox thus supports σ‐hole are same.
Language: Английский
Citations
23
The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(23), P. 15771 - 15782
Published: Nov. 17, 2022
An electrochemical method has been developed to synthesize 2,2-disubstituted indolin-3-ones under mild conditions. A series of nucleophiles have added the 2-arylindole-3-ones, generated in situ metal-free oxidative dearomatization 2-arylindoles, afford 3-carbonyl indoles with heteroquaternary centers 57-79% yields.
Language: Английский
Citations
23
Chemical Communications, Journal Year: 2023, Volume and Issue: 59(9), P. 1217 - 1220
Published: Jan. 1, 2023
A novel protocol for the synthesis of highly functionalized benzo[b][1,5]diazocin-6(5H)-one derivatives (BDCOs, 4 and 5) from 2-aryl-1H-indoles 1,1-enediamines was developed via a complex cascade reactions including regioselective free radical oxidation, 1,2-addition imine, imine-enamine tautomerization, intramolecular cyclization, ring expansion. The reaction enabled by refluxing mixture two substrates in presence di-tert-butyl peroxide (DTBP) as an oxidant anhydrous CuI catalyst toluene under argon protection. Consequently, series BDCOs (4 were synthesized with high regioselectivity good yield. This can be used one-pot oxidative annulation rather than multi-step reaction, which is suitable both combinatorial parallel syntheses BDCOs.
Language: Английский
Citations
12
Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(49)
Published: June 20, 2023
Benzamide-derived organochalcogens (chalcogen=S, Se, and Te) have shown promising interest in biological synthetic chemistry. Ebselen molecule derived from benzamide moiety is the most studied organoselenium. However, its heavier congener organotellurium under-explored. Here, an efficient copper-catalyzed atom economical method has been developed to synthesize 2-phenyl-benzamide tellurenyl iodides by inserting a tellurium into carbon-iodine bond of 2-iodobenzamides one pot with 78-95 % yields. Further, Lewis acidic nature Te center basic nitrogen synthesized 2-Iodo-N-(quinolin-8-yl)benzamide enabled them as pre-catalyst for activation epoxide CO2 at 1 atm preparation cyclic carbonates TOF TON values 1447 h-1 4343, respectively, under solvent-free conditions. In addition, 2-iodo-N-(quinolin-8-yl)benzamide also used activating anilines form variety 1,3-diaryl ureas up 95 yield. The mechanistic investigation mitigation done 125 NMR HRMS studies. It seems that reaction proceeds via formation catalytically active Te-N heterocycle, ebtellur intermediate which isolated structurally characterized.
Language: Английский
Citations
11
Synlett, Journal Year: 2023, Volume and Issue: 34(13), P. 1539 - 1548
Published: Jan. 26, 2023
Abstract 2,2-Disubstituted indoxyls are commonly found within natural products and bioactive molecules. Among the numerous methods to access such motifs, dearomative transformation of indoles represents an attractive approach. Despite much development, a potential gap exists in oxidative union readily accessible 2-substituted with nucleophilic partners, where general accommodating 2-alkyl substitution broad range nucleophiles is lacking. Herein, we describe development user-friendly solution this challenge highlight its utility synthesis complex alkaloids. 1 Introduction 2 Synthesis Indoxyls via Dearomatization Indoles: Background 3 Oxidative 2-Alkylindoles Indoxyls: Development 4 Selected Scope Preliminary Investigations toward Asymmetric Coupling 5 Application Total Complex Alkaloids 6 Conclusions
Language: Английский
Citations
6
The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(8), P. 5589 - 5605
Published: April 5, 2024
Diversity-oriented synthesis strategy for the efficient assembly of indole-fused polycyclic scaffolds via rhodium-catalyzed NH-indole-directed C–H coupling with propargylic alcohol derivatives in a regioselective manner was developed. Five 2-phenyl-1H-indole-embedded core skeletons were synthesized. In particular, three different exo-olefin-containing polycycles realized, which may be manipulated further chemistry.
Language: Английский
Citations
1
Beilstein Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 20, P. 1292 - 1297
Published: June 4, 2024
Redox active phenotellurazine catalysts have been recently utilized in two different cross-dehydrogenative coupling reactions. In this study, we revisit the design of redox catalysts. particular, investigate level cooperativity between Te- and N-centers, effect secondary versus tertiary heterocyclic non-heterocyclic structures, substitution patterns on catalytic activity.
Language: Английский
Citations
1
Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(35), P. 7074 - 7091
Published: Jan. 1, 2024
The present review highlights the dearomatization of indoles by oxidizing C–H bonds for constructing oxindoles skeletons. Various synthetic approaches have been summarized followed their applications in indole alkaloids and bioactive compounds.
Language: Английский
Citations
1
Synlett, Journal Year: 2023, Volume and Issue: 35(09), P. 967 - 972
Published: Dec. 11, 2023
Abstract Metal-free aromatic amines have been utilized recently as redox-active catalysts in various oxidative coupling reactions. In this study, we investigated a series of and their potential redox catalytic activity, particular compared to our previously reported amino-Te(II) catalysts. The O2-mediated cross-dehydrogenative phenothiazination phenols was benchmark test reaction, well the indoles. We thus identified proton sponge an effective amine catalyst. It moreover found that although displays clear it is generally less active than phenotellurazine insights provided by study should guide future research efforts for development innovative redox-catalyzed
Language: Английский
Citations
1
Tetrahedron, Journal Year: 2024, Volume and Issue: 167, P. 134242 - 134242
Published: Sept. 2, 2024
Language: Английский
Citations
0