Unleashing Selective Reduction and Reductive Methylation of N-Heterocycles Using Methanol via Strategic Reaction Condition Modulation

ACS Catalysis, Год журнала: 2025, Номер unknown, С. 3008 - 3022

Опубликована: Фев. 5, 2025

Язык: Английский

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Direct carbonyl reductive functionalizations by diphenylphosphine oxide

Science Advances, Год журнала: 2025, Номер 11(6)

Опубликована: Фев. 7, 2025

Reductive functionalization of aldehydes and ketones is one the most challenging but ultimately rewarding areas in synthetic chemistry related sciences. We report a simple extremely versatile carbonyl reductive strategy achieving direct, highly selective, efficient amination, etherification, esterification, phosphinylation reactions (hetero)aryl ketones, which are or unattainable to achieve by traditional strategies, using only diphenylphosphine oxide an inorganic base. It enables modular synthesis functionally structurally diverse tertiary amines, ethers, esters, phosphine oxides, etc., as well pesticides, drug intermediates, pharmaceuticals. Compared phosphorus-mediated name reactions, this firstly transformed C═O bonds into C-element single bonds. Mechanistically, phosphinates formed undergo unconventional nucleophilic substitution at C atom within their C─O─P unit. Thus, work provides important strides field aldehydes/ketones, transformation, various fundamental reactions.

Язык: Английский

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Selective Transfer Hydrogenation of C=O and Conjugated C=C Bonds Using An NHC‐Based Pincer (CNC)Mn^I Complex in Methanol**

ChemSusChem, Год журнала: 2023, Номер 16(18)

Опубликована: Июнь 8, 2023

Base metal catalyzed transfer hydrogenation reactions using methanol is highly challenging. Employing a single N-heterocyclic carbene (NHC)-based pincer (CNC)MnI complex, chemoselective and double of α, β-unsaturated ketones to saturated or alcohols by utilizing as the hydrogen source disclosed. The protocol was tolerant towards selective C=C C=O bonds in presence several other reducible functional groups led synthesis biologically relevant molecules natural products. Notably, this first report Mn-catalyzed carbonyl with methanol. Several control experiments, kinetic studies, Hammett density theory (DFT) calculations were carried out understand mechanistic details catalytic process.

Язык: Английский

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Utilization of methanol for condensation interrupted chemoselective transfer hydrogenation of CC, CO, and CN bonds under low catalyst loading

Organic Chemistry Frontiers, Год журнала: 2023, Номер 10(9), С. 2274 - 2286

Опубликована: Янв. 1, 2023

Selective transfer hydrogenation (TH) of unsaturated molecules using methanol is challenging as the in situ generated formaldehyde prone to react with active methylene ( C -methylation) or amine N core desired product.

Язык: Английский

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2-(2-Benzimidazolyl)pyridine Mn(I) Complexes: Synthesis and Exploration of Catalytic Activity toward Synthesis of Pyrimidine and Quinoline

Organometallics, Год журнала: 2023, Номер 42(14), С. 1793 - 1802

Опубликована: Май 11, 2023

A series of phosphine-free benzimidazole and pyridine-containing bidentate Mn(I) complexes were synthesized. Among them, Mn1 complex bearing a proton-responsive 2-hydroxypyridine-appended ligand was found to be highly effective for the synthesis different N-heterocycles utilizing alcohols. Employing significantly lower catalyst loading (0.05 mol %), several substituted pyrimidines quinolines effectively The lactim–lactam acid–base equilibrium 2-hydroxypyridine fragment, role countercation base, effect externally added ligands investigated. probable catalytic cycle proposed based on basis various control experiments kinetic studies.

Язык: Английский

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Reductive Aminomethylation Using Ammonium Formate and Methanol as N1 and C1 Source: Direct Synthesis of Mono- and Di-Methylated Amines

ACS Catalysis, Год журнала: 2024, Номер 14(8), С. 5847 - 5857

Опубликована: Апрель 2, 2024

An Ir(III) complex catalyzed single and dual reductive amination followed by N-methylation of aldehydes ketones to synthesize N,N-dimethyl as well N-methyl tertiary amines, respectively, utilizing ammonium formate methanol N1 C1 sources is reported. The protocol was efficiently extended a tandem amination/N-methylation/cyclization keto acids/esters leading lactams. A broad substrate scope, synthesis bioactive molecules, also demonstrated. Control experiments, kinetic studies, DFT calculations were performed based on which plausible mechanism proposed.

Язык: Английский

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N,N-Dialkylation of Acyl Hydrazides with Alcohols Catalyzed by Amidato Iridium Complexes via Borrowing Hydrogen

Organometallics, Год журнала: 2023, Номер 42(18), С. 2623 - 2631

Опубликована: Апрель 1, 2023

Direct N,N-dialkylation of acyl hydrazide catalyzed by a series amidato iridium complexes bearing an electron-donating group in the ligand using methanol or ethanol as alkyl reagent under weak base conditions (10 mol % KHCO3) is described. A wide range derivatives are converted to corresponding N,N-dialkylated products excellent yields (38 examples, ≤96%). On basis control experiments and nuclear magnetic resonance studies, plausible mechanism was proposed. The experimental results indicate that ortho groups on phenyl moiety picolinamide play crucial role catalytic activity.

Язык: Английский

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Half-sandwich ruthenium complexes with acylhydrazone ligands: synthesis and catalytic activity in the N-alkylation of hydrazides

Dalton Transactions, Год журнала: 2023, Номер 53(6), С. 2797 - 2806

Опубликована: Дек. 29, 2023

Novel half-sandwich ruthenium complexes termed [(

Язык: Английский

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Synthesis and catalytic activity of half‐sandwich iridium complexes with acylhydrazone ligands for N‐alkylation of hydrazides under mild conditions

Applied Organometallic Chemistry, Год журнала: 2024, Номер 38(6)

Опубликована: Апрель 14, 2024

A new [Cp*IrClL] half‐sandwich iridium complex was successfully synthesized by coordinating an acylhydrazone ligand with [Cp*IrCl 2 ] , followed comprehensive characterization using various spectroscopic and analytical techniques. Complex 3 subjected to crystal structure analysis, revealing that the coordinates through bidentate coordination involving imidolate oxygen imine nitrogen atoms. This interaction resulted in formation of a pseudo ‐octahedral geometry center. The complexes 1 – 4 which are stable presence air moisture, exhibit significant catalyst performance N‐alkylation reactions hydrazides under gentle reaction conditions. catalyzes types alcohols undergo acyl via one‐pot method, yielding diverse N‐alkylated hydrazide derivatives. displayed exceptional catalytic efficiency, broad variety substrates, conditions, indicating its potential for industrial applications.

Язык: Английский

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Regioselective Ring Opening of Epoxide with Alcohols: A Selective Route to α‐Alkylated Ketones and β‐Alkylated Secondary Alcohols

ChemCatChem, Год журнала: 2024, Номер 16(16)

Опубликована: Апрель 17, 2024

Abstract Herein, we demonstrated an effective protocol for the regioselective ring opening of epoxides with alcohols. By following this strategy, both α‐alkylated ketones and β‐alkylated secondary alcohols were selectively obtained by changing reaction parameters. Compared to previously reported protocols, methodology was operated using considerably lower base at temperature. Notably, a wide array substrates tolerance different functional groups demonstrated. A series control experiments deuterium‐labelling performed understand catalytic process.

Язык: Английский

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