Enable biomass-derived alcohols mediated alkylation and transfer hydrogenation

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Aug. 15, 2024

A single-atom catalyst with generally regarded inert Zn–N4 motifs derived from ZIF-8 is unexpectedly efficient for the activation of alcohols, enabling alcohol-mediated alkylation and transfer hydrogenation. C-alkylation nitriles, ketones, N-heterocycles, amides, keto acids, esters, N-alkylation amines amides all go smoothly developed method. Taking α-alkylation nitriles alcohols as an example, starts (1) nitrogen-doped carbon support catalyzed dehydrogenation into aldehydes, which further condensed to give vinyl followed by (2) hydrogenation C=C bonds in on sites. The experimental results DFT calculations reveal that Lewis acidic Zn-N4 sites promote step activating alcohols. This first example highly catalysts various organic transformations biomass-derived alkylating reagents hydrogen donors. Using carbonyl compounds or synthesis α-alkylated appealing a sustainability perspective. Here, acting acid effectively activates thus promoting reactions using both

Language: Английский

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Recent Developments of Transition‐Metal‐Catalyzed Cross‐Coupling of Nitriles and Alcohols

ChemistrySelect, Journal Year: 2024, Volume and Issue: 9(32)

Published: Aug. 22, 2024

Abstract Cross‐coupling of nitriles and alcohols offers an environmentally friendly atom‐economical method for the synthesis various valuable compounds. These compounds include α ‐alkylated ‐olefinated nitriles, primary amines, imines, N ‐alkylation amides, ‐heterocycles, δ ‐hydroxynitriles, olefins, etc . Herein, we have reviewed recent developments (from 2013–date) transition‐metal‐catalyzed cross‐coupling alcohols. A number transition metal complexes such as noble metals Ru Ir, well base Mn, Fe, Co, Ni are presented. Moreover, different product types, reaction conditions mechanisms discussed to understand catalyst development.

Language: Английский

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Cobalt(III) Complexes of Pyridine-Functionalized Chelating NHC Ligands: Effective Catalysts for the Olefination of Alcohols Using Sulfones

Organometallics, Journal Year: 2024, Volume and Issue: 43(13), P. 1482 - 1489

Published: June 26, 2024

Several air-stable cobalt(III) complexes 1a-d featuring pyridine-functionalized NHC ligand systems were synthesized and completely characterized. These then explored as phosphine-free catalysts for the olefination of alcohols with sulfones, among studied here, benzimidazolylidene-supported 1b complex acetylacetonate (acac) a labile co-ligand was noted to be most active one, which also successful broad range sulfones providing diverse olefins. It is important mention that this first example such protocol catalyzed by cobalt. Furthermore, utility present demonstrated gram-scale reaction postsynthetic modifications obtained compounds. Finally, based on various control experiments including detection intermediates kinetic studies, plausible mechanism proposed.

Language: Английский

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Ruthenium‐Catalyzed α‐Alkylation of Arylacetonitriles with Primary Alcohols: N‐heterocyclic Carbene‐Amine's Promotional Influence

ChemistrySelect, Journal Year: 2025, Volume and Issue: 10(7)

Published: Feb. 1, 2025

Abstract Transition‐metal‐catalyzed α‐alkylation of nitriles with alcohols is an environmentally benign reaction, and the development simple efficient catalysts for this transformation a growing area research. In study, we report serial bidentate N ‐heterocyclic carbene (NHC) ruthenium complexes different extra donors alcohols. Through adjusting backbone NHC ligands, catalytic activities these could be controlled. The complex ( Ru3 ) bearing amine donor benzimidazolium exhibited highest activity. A large variety α‐alkylated were obtained in 30%–88% yields, by using 1 mol% amount Cs 2 CO 3 (20 mol%). Detailed control experiments deuterium‐labeling suggested that reaction proceeds via borrowing hydrogen pathway.

Language: Английский

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Mechanistic Investigations on Cp*Co^III-Catalyzed Quinoline Transfer Hydrogenation with Formic Acid

ACS Catalysis, Journal Year: 2024, Volume and Issue: unknown, P. 17556 - 17570

Published: Nov. 14, 2024

The mechanism of the quinoline transfer hydrogenation (TH) by aqueous HCOOH under action [Cp*Co(quinNH2)I]+ (A*; quinNH2 = 8-aminoquinoline) has been investigated a combination experiments and density functional theory (DFT) calculations. Variable-temperature (−40 to 20 °C) 1H NMR in absence substrate shows rapid equilibration between A* formate complex [Cp*Co(quinNH2)(O2CH)]+ (B*) upon addition HCOOH/NEt3 MeOH, yielding ΔH° 1.49 ± 0.03 kcal mol–1 ΔS° 1.92 0.06 cal K–1. This equilibrium mixture slowly converts decarboxylation deprotonation paramagnetic (S 1) [Cp*Cp(quinNH2)] (C*), indirectly identified derivatization [Cp*Co(CNtBu)2] further I2 oxidation [Cp*Co(CNtBu)2I](I3). rate law [Cp*Co(quinNH2)I]+-catalyzed 8-methylquinoline (8MQ) TH with D2O at 80 °C order one for catalyst zero HCOOH, constant k (1.52 0.05) × 10–2 s–1 L. (Q) (k (2.04 L) selectively yields tetrahydroquinoline doubly D-labeled C3 position ([3,3-D2]-THQ). Under same conditions, DCOOD [2,3,3,4-D4]-THQ (6.6 0.6) 10–3 L (KIE kH/kD 3.1 0.5), while H2O [2,4-D2]-THQ. DFT calculations Cp model system point catalytic cycle both diamagnetic intermediates. A key aspect is that H atom as hydride metal center, converting [CpCo(quinNH2)(O2CH)]+ (B) [CpCo(quinNH2)H]+ (D), faster than its proton yield [CpCp(quinNH2)] (C). variance closely related 8-hydroxyquinoline ligand (ACS Catal. 2021, 11, 11906–11920), underlining decisive roles reaction medium selection dehydrogenation pathway.

Language: Английский

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Revealing the reaction mechanism of the alkylation of nitrile catalyzed by a bifunctional Co(III)-NHC complex: A DFT study

Inorganic Chemistry Communications, Journal Year: 2024, Volume and Issue: unknown, P. 113800 - 113800

Published: Dec. 1, 2024

Language: Английский

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