Homogeneous manganese-catalyzed hydrogenation and dehydrogenation reactions

Chem, Год журнала: 2020, Номер 7(5), С. 1180 - 1223

Опубликована: Дек. 9, 2020

Язык: Английский

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Manganese-catalyzed hydrogenation, dehydrogenation, and hydroelementation reactions

Chemical Society Reviews, Год журнала: 2022, Номер 51(11), С. 4386 - 4464

Опубликована: Янв. 1, 2022

The emerging field of organometallic catalysis has shifted towards research on Earth-abundant transition metals due to their ready availability, economic advantage, and novel properties. In this case, manganese, the third most abundant transition-metal in Earth's crust, emerged as one leading competitors. Accordingly, a large number molecularly-defined Mn-complexes been synthesized employed for hydrogenation, dehydrogenation, hydroelementation reactions. regard, catalyst design is based three pillars, namely, metal-ligand bifunctionality, ligand hemilability, redox activity. Indeed, developed catalysts not only differ chelating atoms they possess but also working principles, thereby different turnover numbers product molecules. Hence, critical assessment molecularly defined manganese terms atoms, reaction conditions, mechanistic pathway, significant. Herein, we analyze complexes catalytic activity, versatility allow multiple transformations routes convert substrates target This article will be helpful get significant insight into design, aiding design.

Язык: Английский

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Alcohols as Substrates in Transition-Metal-Catalyzed Arylation, Alkylation, and Related Reactions

Chemical Reviews, Год журнала: 2024, Номер 124(9), С. 6078 - 6144

Опубликована: Апрель 17, 2024

Alcohols are abundant and attractive feedstock molecules for organic synthesis. Many methods their functionalization require them to first be converted into a more activated derivative, while recent years have seen vast increase in the number of complexity-building transformations that directly harness unprotected alcohols. This Review discusses how transition metal catalysis can used toward this goal. These broadly classified three categories. Deoxygenative functionalizations, representing derivatization C–O bond, enable alcohol act as leaving group formation new C–C bonds. Etherifications, characterized by O–H represent classical reactivity has been modernized include mild reaction conditions, diverse partners, high selectivities. Lastly, chain reactions described, wherein acts mediator formal C–H alkyl backbone. Each these classes transformation will discussed context intermolecular arylation, alkylation, related reactions, illustrating alcohols harnessed

Язык: Английский

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Selective Catalytic Synthesis of α-Alkylated Ketones and β-Disubstituted Ketones via Acceptorless Dehydrogenative Cross-Coupling of Alcohols

Organic Letters, Год журнала: 2021, Номер 23(3), С. 869 - 875

Опубликована: Янв. 21, 2021

Herein, a phosphine-free pincer ruthenium(III) catalyzed β-alkylation of secondary alcohols with primary to α-alkylated ketones and two different β-branched are reported. Notably, this transformation is environmentally benign atom efficient H2O H2 gas as the only byproducts. The protocol extended gram-scale reaction for functionalization complex vitamin E cholesterol derivatives.

Язык: Английский

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Towards ligand simplification in manganese-catalyzed hydrogenation and hydrosilylation processes

Coordination Chemistry Reviews, Год журнала: 2022, Номер 458, С. 214421 - 214421

Опубликована: Янв. 31, 2022

Язык: Английский

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Divergent Synthesis of Alcohols and Ketones via Cross‐Coupling of Secondary Alcohols under Manganese Catalysis

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(26)

Опубликована: Апрель 21, 2023

A homogeneous manganese-catalyzed cross-coupling of two secondary alcohols for the divergent synthesis γ-disubstituted and β-disubstituted ketones is reported. Employing well-defined Mn-MACHOPh as catalyst, this novel protocol has a broad substrate scope with good functional group tolerance affords diverse library valuable disubstituted in moderate to yields. The strong influence reaction temperature on selective formation alcohol products was theorized preliminary DFT studies. Studies have shown that Gibbs free energy thermodynamically more favourable than corresponding at lower temperature.

Язык: Английский

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Well-Defined Bis(NHC)Mn(I) Complex Catalyzed Tandem Transformation of α,β-Unsaturated Ketones to α-Methylated Ketones Using Methanol

ACS Catalysis, Год журнала: 2022, Номер 12(19), С. 12444 - 12457

Опубликована: Сен. 28, 2022

Tandem transformation of α,β-unsaturated ketones to α-methylated by utilizing methanol as both the hydrogen and C1 sources is reported in presence a phosphine-free bis-N-heterocyclic carbene-Mn(I) (bis-NHC-Mn(I)) catalyst. The dehydrogenative coupling between produces corresponding along with 1 equiv formaldehyde water. Among different bis-NHC-Mn(I) complexes, ethyl wingtip-substituted complex triflate counteranion showed highest catalytic activity. This system was highly effective for reductive methylation wide variety substrates including aromatic, heteroaromatic, aliphatic straight chains containing ketones. Notably, this methodology led synthesis pharmaceutically important drug molecules such eperisone lanperisone. Several control experiments, kinetic studies, Hammett density functional theory (DFT) calculations were carried out understand tandem process.

Язык: Английский

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Recent Advances for Alkylation of Ketones and Secondary Alcohols Using Alcohols in Homogeneous Catalysis

Advanced Synthesis & Catalysis, Год журнала: 2022, Номер 364(18), С. 3100 - 3121

Опубликована: Июль 4, 2022

Abstract The alkylation of ketones or secondary alcohols using as alkylating agents via hydrogen borrowing strategy presents a powerful method for the synthesis ɑ‐alkylated ketones. In this review, we summarize progress catalyzed by Ir, Pd, Rh, Ru, Mn, Fe, Co, Ni, and Cu catalysts α‐alkylation with cross‐coupling from 2017 to 2021. A wide range (aromatic aliphatic ketones) (benzylic primary alcohols, aromatic alkenyl diols) are well tolerated. Furthermore, also discuss current challenges propose perspectives on coming development in filed. objective present review is give an overview recent advances β‐alkylation alcohols. Finally, hope that will inspirations magnified image

Язык: Английский

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Manganese‐Catalyzed Chemoselective Coupling of Secondary Alcohols, Primary Alcohols and Methanol

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(17)

Опубликована: Фев. 27, 2023

Herein, we report a manganese-catalyzed three-component coupling of secondary alcohols, primary alcohols and methanol for the synthesis β,β-methylated/alkylated alcohols. Using our method, series 1-arylethanol, benzyl alcohol derivatives, undergo sequential efficiently to construct assembled with high chemoselectivity in moderate good yields. Mechanistic studies suggest that reaction proceeds via methylation benzylated intermediate generate final product.

Язык: Английский

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Surmounting Alkoxide Trap Strategy: N-Heterocyclic Carbene Chromium(0)-Catalyzed C-Alkylation between Alcohols

ACS Catalysis, Год журнала: 2023, Номер 13(19), С. 12481 - 12493

Опубликована: Сен. 8, 2023

The crucial role of the alkoxide trap problem and impact oxidation state chromium center were demonstrated on catalytic activity due to d-wall issue. Through strategy surmounting trap, a Cr(0) catalyst was presented herein for efficient C-alkylation between alcohols via borrowing hydrogen/hydrogen autotransfer. synthesized bis-(N-heterocyclic carbene)-Cr(0) system shows an performance (40 examples, up 96% yield). Only loading cheap readily available base NaOH is effective enough reaction. Compared with Cr(III)/Cr(II), can well avoid d-p π interaction in key metal-alkoxide intermediate, thus overcoming thermodynamic sink problem. It plausible that Cr(III) systems need be reduced Cr(II) weakening effect enhancing by using reductive strong bases. This should helpful development nonprecious transition metal catalysts.

Язык: Английский

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