Electron transfer catalysis mediated by 3d complexes of redox non-innocent ligands possessing an azo function: a perspective

Dalton Transactions, Journal Year: 2023, Volume and Issue: 52(43), P. 15627 - 15646

Published: Jan. 1, 2023

It was first reported almost two decades ago that ligands with azo functions are capable of accepting electron(s) upon coordination to produce azo-anion radical complexes, thereby exhibiting redox non-innocence. Over the past decades, there have been numerous reports such complexes along their structures and diverse characteristics. The ability a coordinated function accept one or more electron(s), acting as an electron reservoir, is currently employed carry out transfer catalysis since they can undergo transformation at mild potentials due presence energetically accessible energy levels. cooperative involvement non-innocent ligand(s) containing group metal centre adjust modulate Lewis acidity latter through selective ligand-centred events, manipulating capacity bind substrate. We summarized list row transition iron, cobalt, nickel, copper zinc incorporating exploited catalysts effectuate sustainable synthesis wide variety useful chemicals. These include ketazines, pyrimidines, benzothiazole, benzoxazoles, N-acyl hydrazones, quinazoline-4(3)H-ones, C-3 alkylated indoles, N-alkylated anilines heteroamines. reaction pathways, demonstrated by catalytic loops, reveal ligand act sink in initial steps bring about alcohol oxidation thereafter, serve pool final products either via HAT PCET processes.

Language: Английский

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Ruthenium complexes of redox non-innocent aryl-azo-oximes for catalytic α-alkylation of ketones and synthesis of 2-substituted quinolines

New Journal of Chemistry, Journal Year: 2024, Volume and Issue: 48(18), P. 8181 - 8194

Published: Jan. 1, 2024

In this work we demonstrated the synthesis, characterisation and catalytic applications of Ru( ii )–azooximato complexes. This is first report where arylazooximato complexes a transition metal are used in C–C bond formation reactions.

Language: Английский

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One-Pot Sustainable Synthesis of Highly Substituted Pyrimidines via Acceptorless Dehydrogenative Annulation of Alcohols Using Pincer Ni(II)–NNS Catalysts

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(16), P. 11148 - 11160

Published: Aug. 1, 2024

We report an efficient and sustainable synthesis of highly substituted pyrimidines promoted by nickel(II)-NNS pincer-type complexes via acceptorless dehydrogenative annulations readily available alcohols, malononitrile, guanidine/benzamidine salt under eco-friendly conditions for the first time. Different sets Ni(II) (

Language: Английский

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Generation and application of carbodiimide anions: efficient construction of 2-aminopyrimidines via a cascade [4 + 2] annulation/aromatization sequence

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(23), P. 5863 - 5869

Published: Jan. 1, 2023

This work disclosed an unprecedented carbodiimide anion participated cascade [4 + 2] annulation/aromatization reaction, affording efficient method for synthesizing 2-aminopyrimidines.

Language: Английский

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Zn(II)-Stabilized Azo-Anion Radical-Catalyzed Dehydrogenative Synthesis of Olefins

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 16, 2024

Herein, we describe a Zn-catalyzed atom-economical, inexpensive, and sustainable method for preparing broad spectrum of substituted olefins utilizing alcohols as the main precursor. Using Zn(II) complex [ZnLCl2] (1) redox-noninnocent ligand 2-((4-chlorophenyl)diazenyl)-1,10-phenanthroline (L), various (E)-olefins were prepared in good yields by coupling with sulfones aryl cyanides under an inert atmosphere. Under aerial atmosphere, vinyl nitriles isolated up to 82% yield reacting benzyl presence 1. Control experiments mechanistic investigation indicate active involvement aryl-azo electron hydrogen reservoir, permitting 1 perform promising catalyst.

Language: Английский

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Synthesis of 2‐amino‐4‐aryl‐6‐styrylpyrimidines through aza‐Michael addition/nucleophilic addition/dehydrogenation cascade reactions

Journal of Heterocyclic Chemistry, Journal Year: 2023, Volume and Issue: 60(12), P. 1999 - 2008

Published: Sept. 17, 2023

Abstract An efficient method for the synthesis of 2‐amino‐4‐aryl‐6‐styrylpyrimidines by reactions various distyryl ketones with guanidine hydrochloride through aza‐Michael addition/nucleophilic addition/dehydrogenation cascade processes is described. The salient features this protocol are use easy‐to‐obtain substrates, transition‐metal‐free system, mild reaction conditions, high atom economy, wide substrate scope, satisfactory yield, and simple work‐up procedures.

Language: Английский

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Nickel-Catalyzed Sustainable and Selective Alkylation of Alcohols to α-Alkylated Ketones via Borrowing Hydrogen Approach

Synlett, Journal Year: 2022, Volume and Issue: 34(06), P. 635 - 644

Published: Aug. 30, 2022

Abstract Herein, we report a nickel-catalyzed sustainable, environment­-friendly, and economically affordable borrowing hydrogen approach (BHA) for synthesizing various α-alkylated ketones via dehydro­genative coupling of primary secondary alcohols. Using well-­defined, air-stable, inexpensive, easy-to-prepare four-coordinate macrocyclic Ni(II)-catalyst [Ni(MeTAA)] tetra-aza ligand (tetramethyltetraaza[14]annulene (H2MeTAA)), series were prepared in good yields. A few control reactions, including deuterium-labelling experiments, performed to unveil the reaction mechanism.

Language: Английский

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Triazines, tetrazines and fused ring polyaza systems

Progress in heterocyclic chemistry, Journal Year: 2023, Volume and Issue: unknown, P. 471 - 491

Published: Jan. 1, 2023

Language: Английский

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