Silver-Exchanged Zeolite Y Catalyzes a Selective Insertion of Carbenes into C–H and O–H Bonds DOI Creative Commons

Yongkun Zheng,

Alejandro Vidal‐Moya, Juan Carlos Hernández‐Garrido

et al.

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: unknown

Published: Nov. 3, 2023

Commercially available zeolite Y modulates the catalytic activity and selectivity of ultrasmall silver species during Buchner reaction carbene addition to methylene hydroxyl bonds, by simply exchanging counter cations framework. The acts as a macroligand tune site, enabling use this cheap recyclable solid catalyst for in situ formation carbenes from diazoacetate selective insertion different C-H (i.e., cyclohexane) C-O water) bonds. amount can be low ≤0.1 mol % silver. Besides, reactivity allows deeply drying HY framework making strongly adsorbed water molecules react with formed carbenes.

Language: Английский

Silver‐Catalyzed Dearomative [2π+2σ] Cycloadditions of Indoles with Bicyclobutanes: Access to Indoline Fused Bicyclo[2.1.1]hexanes** DOI
Lei Tang, Yuanjiu Xiao, Feng Wu

et al.

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(48)

Published: Oct. 12, 2023

Bicyclo[2.1.1]hexanes (BCHs) are becoming ever more important in drug design and development as bridged scaffolds that provide underexplored chemical space, but difficult to access. Here a silver-catalyzed dearomative [2π+2σ] cycloaddition strategy for the synthesis of indoline fused BCHs from N-unprotected indoles bicyclobutane precursors is described. The strain-release operates under mild conditions, tolerating wide range functional groups. It capable forming with up four contiguous quaternary carbon centers, achieving yields 99 %. In addition, scale-up experiment synthetic transformations cycloadducts further highlighted utility.

Language: Английский

Citations

76
Spiroindoles as Intermediates/Products in Transition Metal-Catalyzed Dearomatization of Indoles DOI
Floris Buttard, Xavier Guinchard

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(14), P. 9442 - 9475

Published: July 3, 2023

Spirocyclic indole derivatives are fascinating tridimensional molecular scaffolds from both a synthetic and biological point of view. Among the many strategies developed to access these structures, transition metal catalysis has recently led impressive advances, especially relying on unique reactivity dearomatized spirocyclic intermediates. These species can indeed evolve toward or nonspirocyclic products through rearomatization-driven processes, which at same time highly challenging control but also source large structural diversity. This review highlights most prominent methods past decade that involve spirocyclization tethered functional group may be activated by metal, leading rearomatized products. The discussion is particularly focused spiroindoleninium intermediate complex mechanistic features regarding its evolution, dependent catalytic systems.

Language: Английский

Citations

44
C(sp2)–H cyclobutylation of hydroxyarenes enabled by silver-π-acid catalysis: diastereocontrolled synthesis of 1,3-difunctionalized cyclobutanes DOI Creative Commons
Lei Tang, Qin-An Huang, Feng Wu

et al.

Chemical Science, Journal Year: 2023, Volume and Issue: 14(36), P. 9696 - 9703

Published: Jan. 1, 2023

Ring-opening of bicyclo[1.1.0]butanes (BCBs) is emerging as a powerful strategy for 1,3-difunctionalized cyclobutane synthesis. However, reported radical strain-release reactions are typically plagued with diastereoselectivity issues. Herein, an atom-economic protocol the highly chemo- and diastereoselective polar ring-opening BCBs hydroxyarenes catalyzed by π-acid catalyst AgBF4 has been developed. The use readily available starting materials, low loading, high selectivity (up to >98 : 2 d.r.), broad substrate scope, ease scale-up, versatile functionalizations products make this approach very attractive synthesis 1,1,3-trisubstituted cyclobutanes. Moreover, control experiments theoretical calculations were performed illustrate reaction mechanism selectivity.

Language: Английский

Citations

42
Biogenic synthesis of silver nanoparticles/reduced graphene oxide (AgNPs/rGO) mediated Nephelium lappaceum leaf extract as an effective solid acid catalyst for liquid-phase benzene nitration DOI Creative Commons
Dewi Lestari, Akhmad Syoufian, Poedji Loekitowati Hariani

et al.

Results in Chemistry, Journal Year: 2025, Volume and Issue: 13, P. 102014 - 102014

Published: Jan. 1, 2025

Language: Английский

Citations

1
A new silver coordination polymer based on 4,6-diamino-2-pyrimidinethiol: synthesis, characterization and catalytic application in asymmetric Hantzsch synthesis of polyhydroquinolines DOI Creative Commons

Noorullah Hussain–Khil,

Arash Ghorbani‐Choghamarani, Masoud Mohammadi

et al.

Scientific Reports, Journal Year: 2021, Volume and Issue: 11(1)

Published: Aug. 2, 2021

Abstract A highly efficient and stable heterogeneous coordination polymer (CP) was successfully prepared by hydrothermal combination of silver 4,6-diamino-2-pyrimidinethiol. The characterized FT-IR, XRD, TGA, SEM, EDX, X-ray mapping Nitrogen adsorption–desorption analysis. Ag–CP exhibit excellent catalytic activity in multicomponent Hantzsch synthesis polyhydroquinolines under mild reaction conditions relatively short times. heterogeneity the catalyst confirmed hot filtration test; also, reused for at least four times optimized without any significant loss its activity.

Language: Английский

Citations

54
Palladium-Catalyzed Modular and Enantioselective cis-Difunctionalization of 1,3-Enynes with Imines and Boronic Reagents DOI
Qing He, Lei Zhu,

Zhen‐Hong Yang

et al.

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(43), P. 17989 - 17994

Published: Oct. 20, 2021

Here we report that a palladium(0) complex can mediate the unprecedented intermolecular coupling reaction of 1,3-enynes and N-sulfonylimines regio- stereoselectively, resultant palladium(II) species undergo cascade Suzuki with organoboronic reagents. The substrate scope is substantial for asymmetric three-component process, enantioenriched all-carbon tetra-substituted alkene derivatives are efficiently constructed in modular cis-difunctionalized manner. Control experiments density functional theory (DFT) calculations support idea acts as π-Lewis base catalyst by chemoselectively forming η2-complexes moiety 1,3-enynes, thus increasing nucleophilicity alkyne group based on principle vinylogy, to attack imines enantioselectively. preferable formation aza-palladacyclopentene intermediates, via 90° single bond rotation from π-allyl complex, guarantees formal cis-carbopalladation group. In addition, palladium(0)-catalyzed enantioselective reductive 1,3-enyne imine realized using formic acid hydrogen transfer reagent.

Language: Английский

Citations

52
Silver‐Catalyzed Asymmetric Double Desymmetrization via Vinylogous Michael Addition of Prochiral α,α‐Dicyanoalkenes to Cyclopentendiones DOI
Kavita Choudhary, Harshit Joshi,

Shweta Rohilla

et al.

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(20)

Published: Feb. 7, 2024

An asymmetric double desymmetrization methodology has been developed for synthesizing densely functionalized chiral cyclopentylcyclohexane scaffolds. We have constructed four centers, including an all-carbon quaternary stereocenter in a single C-C bond formation event. The high functional-group tolerance and delivers broad range of enantioenriched products. This vinylogous Michael addition reaction prochiral α,α-dicyanocyclohexane to 2,2-disubstituted cyclopentene-1,3-dione is catalyzed by Ag-(R)-DTBM-SEGPHOS catalyst.

Language: Английский

Citations

7
Trifluoromethyl Nonaflate: A Practical Trifluoromethoxylating Reagent and its Application to the Regio‐ and Stereoselective Synthesis of Trifluoromethoxylated Alkenes DOI
Zhichao Lu, Tatsuya Kumon, Gerald B. Hammond

et al.

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(29), P. 16171 - 16177

Published: May 19, 2021

The trifluoromethoxy group has elicited much interest among drug and agrochemical discovery teams because of its unique properties. We developed trifluoromethyl nonafluorobutanesulfonate (nonaflate), TFNf, an easy-to-handle, bench-stable, reactive, scalable trifluoromethoxylating reagent. TFNf is easily safely prepared in a simple process large scale the nonaflyl part can be recovered as fluoride after usage recycled. synthetic potency was showcased with underexplored synthesis various trifluoromethoxylated alkenes, through high regio- stereoselective hydro(halo)trifluoromethoxylation alkyne derivatives such haloalkynes, alkynyl esters, sulfones. merits were further underscored high-yielding smooth nucleophilic trifluoromethoxylation alkyl triflates/bromides primary/secondary alcohols.

Language: Английский

Citations

33
Simple silver(i)-salt catalyzed selective hydroboration of isocyanates, pyridines, and quinolines DOI

Vipin K. Pandey,

Sangita Sahoo,

Arnab Rit

et al.

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(36), P. 5514 - 5517

Published: Jan. 1, 2022

AgSbF6 has been established as an effective catalyst for the hydroboration of structurally and electronically diverse isocyanates under ligand- solvent-free conditions which selectively yielded either N-boryl formamides or methylamines different conditions. Further, various N-heterocycles can be hydroborated using this simple catalytic system; pyridine derivatives undergo preferential 1,4 whereas formation tetrahydroquinoline (after hydrolysis) via complete heterocycle hydrogenation was observed quinolines.

Language: Английский

Citations

24
Hydrogen Source Tuned Regiodivergent Asymmetric Hydroalkylations of 2‐Substituted 1,3‐Dienes with Aldehydes by Cobalt‐Catalysis DOI

Xian‐Wang Zeng,

Jia‐Ni Lin,

Wei Shu

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(23)

Published: April 3, 2024

Abstract Catalytic methods allowing for the reliable prediction and control of diverse regioselectivity along with enantioselectivity to access different regio‐ enantiomers by switching least reaction parameters are one most attractive ways in organic synthesis, which provide enantioenriched architectures from identical starting materials. Herein, a Co‐catalyzed regiodivergent enantioselective reductive hydroalkylation 1,3‐dienes aldehydes has been achieved, furnishing homoallylic alcohol good levels enantioselectivity. The features switch tuned selection proton source. use an acid as source provided asymmetric 1,2‐hydroalkylation products under conditions, yet 4,3‐hydroalkylation were obtained silane hydride This catalytic protocol allows alcohols two continuous saturated carbon centers regio‐, diastereo‐,

Language: Английский

Citations

6