Multi-Hydroxyl POSS Supported Iridium Complexes as a Recyclable Catalyst for Selective Synthesis of N-/C-Substituted Indoles and the Total Synthesis of HIV-1 Fusion Inhibitor DOI
Jiahao Li, Li Chen, Likui Wang

et al.

Published: Jan. 1, 2023

A novel pyridyl-thiadiazole ligand has been designed, synthesized, and employed in the preparation of a heterogeneous iridium catalyst supported on multi-hydroxyl polyhedral oligomeric silsesquioxane. The as-prepared exhibits excellent catalytic activity one-pot cascade selective synthesis N-/C-substituted indole derivatives from amino alcohols via borrowing hydrogen strategy. Meanwhile, it was observed that this approach good functional group tolerance broad substrate scope. Notably, by employing system, an inhibitor against gp41-mediated HIV-1 fusion core structure could be conveniently synthesized 2-aminophenethyl alcohol benzyl 40.6% total yield for only four steps “borrowing hydrogen” Mechanistic explorations showed transformation undergoes processes, involving N/C-alkylation through strategy, oxidative cyclization. Recycling experiments disclosed easily recovered reused at least seven times with TON.

Language: Английский

Harnessing alcohols as sustainable reagents for late-stage functionalisation: synthesis of drugs and bio-inspired compounds DOI
Sourajit Bera, Lalit Mohan Kabadwal, Debasis Banerjee

et al.

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(9), P. 4607 - 4647

Published: Jan. 1, 2024

This review collectively discussed the utilisation of alcohols in various organic transformations and their application toward intermediates drugs, drug derivatives natural product-like molecules.

Language: Английский

Citations

16
Alcohol Dehydrogenation-Triggered Selective C3-Alkylation of Indoles by Homogeneous Azo-aromatic Cobalt Catalysts DOI

kamal kamal,

Manas Khatua, Swati Rani

et al.

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(9), P. 5827 - 5843

Published: April 10, 2023

Herein, we report azo-benzimidazole containing cobalt complexes (1-3) for alcohol dehydrogenation-triggered C3-alkylation of indoles. In 1-3, ligands are redox noninnocent and showed facile irreversible L/L• reduction followed by Co(II)/Co(I) in close-lying potentials. Taking advantage events the first aerial dehydrogenation alcohols to their corresponding carbonyl compounds is explored. Subsequently, indole was studied using as alkylating agents. The developed catalytic protocol found be efficient very selective. It has a broad substrate scope good functional group tolerance. As far aware, it homogeneous catalyst agent. Detailed mechanistic studies, including deuterium labeling experiment, have suggested borrowing hydrogen method indole. coordinated ligand, cooperatively with couple, oxidized alkoxide radical pathway result compound (Scheme 1), which on subsequent condensation generates alkylideneindolenine intermediate "X". Reduction "X" an azo-anion Co(I) resulted C3-alkylated

Language: Английский

Citations

21
A general and robust Ni-based nanocatalyst for selective hydrogenation reactions at low temperature and pressure DOI Creative Commons
Yue Hu, Mingyang Liu, Stephan Bartling

et al.

Science Advances, Journal Year: 2023, Volume and Issue: 9(48)

Published: Dec. 1, 2023

Catalytic hydrogenations are important and widely applied processes for the reduction of organic compounds both in academic laboratories industry. To perform these reactions sustainable practical manner, development applicability non-noble metal–based heterogeneous catalysts is crucial. Here, we report highly active air-stable nickel nanoparticles supported on mesoporous silica (MCM-41) as a general selective hydrogenation catalyst. This catalytic system allows carbonyl compounds, nitroarenes, N-heterocycles, unsaturated carbon─carbon bonds good to excellent selectivity under very mild conditions (room temperature 80°C, 2 10 bar H ). Furthermore, optimal nickel/meso–silicon dioxide catalyst reusable (4 cycles) without loss its activity.

Language: Английский

Citations

20
Amine Functionalized Pincer-like Azo-aromatic Complexes of Cobalt and Their Catalytic Activities in the Synthesis of Quinoline via Acceptorless Dehydrogenation of Alcohols DOI
Bappaditya Goswami, Manas Khatua,

Robindo Chatterjee

et al.

Organometallics, Journal Year: 2023, Volume and Issue: 42(15), P. 1854 - 1868

Published: July 6, 2023

Herein we disclose a series of phosphine-free cobalt(II)-based catalytic systems bearing redox non-innocent amine functionalized azo-aromatic pincer-like ligand for the synthesis quinoline by dehydrogenative oxidation 2-amino benzyl alcohol and subsequent coupling with ketone. All precatalysts were characterized thoroughly using various spectroscopic techniques DFT studies. The protocol was efficient versatile, providing major advances in quinoline. It also found to be applicable gram-scale quinolines as well. Several control experiments, kinetic studies, studies have proposed plausible reaction mechanism where azo-pyridine moiety acts activate α-C–H bond Co(II) → Co(I) reduction leads formation aldehyde. generated aldehyde undergoes base-catalyzed C–C result quinolines. potential controls efficiency precatalysts. Thus, complex 3 most anodic best precatalyst among complexes 1–4.

Language: Английский

Citations

17
Zn(II)‐Stabilized Azo‐Anion Radical Catalyzed Sustainable C−C Bond Formation: Regioselective Alkylation of Fluorene, Oxindole, and Indoles DOI
Subhasree Pal, Amit Kumar Guin, Subhajit Chakraborty

et al.

ChemCatChem, Journal Year: 2024, Volume and Issue: 16(10)

Published: Feb. 7, 2024

Abstract Herein we report a sustainable approach for the alkylation of ketones, 9 H ‐fluorene, oxindole, and indole using alcohols as alkylating agent catalyzed by well‐defined air‐stable zinc catalyst ( 1 ) tridentate redox non‐innocent arylazo ligand, 2‐((4‐chlorophenyl)diazenyl)‐1,10‐phenanthroline L ). 2–3 mol % efficiently produces substituted α‐alkylated 9‐alkylated fluorenes, C3 ‐alkylated oxindoles, indoles in moderate to good isolated yields. In aerial condition, formation bis(indolyl)methane (BIMs) derivatives were observed when subjected primary alcohols. A few drug molecules containing BIMs prepared The exhibited chemoselectivity during functionalization fluorene with oleyl alcohol β‐citronellol. control experiments, including deuterium labeling performed unveil reaction mechanism indicate that one‐electron reduced azo‐anion radical species [ ]‐formed situ, acts active catalyst. All events occur at redox‐active aryl‐azo which reservoir hydrogen electrons throughout catalytic cycle, keeping Zn(II)‐center template.

Language: Английский

Citations

8
Development of a General and Selective Nanostructured Cobalt Catalyst for the Hydrogenation of Benzofurans, Indoles and Benzothiophenes DOI Creative Commons
Bei Zhou, Vishwas G. Chandrashekhar, Zhuang Ma

et al.

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(10)

Published: Jan. 13, 2023

The selective hydrogenation of benzofurans in the presence a heterogeneous non-noble metal catalyst is reported. developed optimal catalytic material consists cobalt-cobalt oxide core-shell nanoparticles supported on silica, which has been prepared by immobilization and pyrolysis cobalt-DABCO-citric acid complex silica under argon at 800 °C. This novel allows for simple functionalized to 2,3-dihydrobenzofurans as well related heterocycles. versatility reported protocol showcased reduction selected drugs deuteration Further, stability, recycling, reusability Co-nanocatalyst are demonstrated.

Language: Английский

Citations

16
Structurally Well-Defined PC(sp3)P Osmium Pincer Catalysts for Methylation of Alcohols, Indoles, Phenols, and Sulfonamides Using Methanol as a C1 Source DOI Creative Commons
Nandita Biswas, Dmitri Gelman

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(3), P. 1629 - 1638

Published: Jan. 17, 2024

Recent findings show pincer catalysts of osmium superior in a broad spectrum synthetically valuable transformations. This article reports structurally well-defined Os(II)PCsp3P complexes stabilized by functional dibenzobarrelene-based ligand. We describe their organometallic and catalytic properties the hydride transfer reactions. demonstrate that center, covalently locked within 3-dimensional ligand pocket, exhibits strictly predictable coordination behavior redox rigidity while remaining catalytically active owing to potential cooperation with proximate side arm. The described were found as mild selective methylation alcohols, indoles, phenols, sulfonamides using methanol C1 source.

Language: Английский

Citations

5
Nitrogen-Doped Carbon Supported Nanocobalt Catalyst for Hydrogen-Transfer Dearomative Coupling of Quinolinium Salts and Tetrahydroquinolines DOI

Shengting Xu,

Zechun Cai,

Chuyi Liao

et al.

Organic Letters, Journal Year: 2022, Volume and Issue: 24(28), P. 5209 - 5213

Published: July 14, 2022

A nitrogen-doped carbon supported nanocobalt catalyst was developed and successfully applied for the hydrogen-transfer coupling of quinolinium salts tetrahydroquinoline compounds. The selective C6 sites tetrahydroquinolines (THQs) with α quinoline generated a series 2-substituted N-alkyl-tetrahydroquinolines. This catalytic conversion method, which can be employed to synthesize various functionalized tetrahydroquinolines, has several advantages that include excellent hydrogen transfer selectivity, reusable inexpensive catalyst, environmental friendliness.

Language: Английский

Citations

19
Multi-hydroxyl POSS supported iridium complexes as a recyclable catalyst for selective synthesis of N-/C-substituted indoles and the total synthesis of HIV-1 fusion inhibitor DOI
Jiahao Li, Li Chen, Likui Wang

et al.

Journal of Catalysis, Journal Year: 2023, Volume and Issue: 429, P. 115205 - 115205

Published: Nov. 24, 2023

Language: Английский

Citations

12
HFIP-mediated C-3-alkylation of indoles and synthesis of indolo[2,3-b]quinolines & related natural products DOI

Auqib Rashid,

Waseem I. Lone,

Preeti Dogra

et al.

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(17), P. 3502 - 3509

Published: Jan. 1, 2024

An expeditious metal free C-3 alkylation of indoles and its NIS-mediated deviation to indolo[2,3- b ]quinolines is reported. Applications these strategies in accessing bioactive natural products have also been demonstrated.

Language: Английский

Citations

4