Tetraaminocyclopentadienone Iron Complexes as Hydrogenation Catalysts DOI

Ludwig Hackl,

Luong Phong Ho,

Dustin Bockhardt

et al.

Organometallics, Journal Year: 2022, Volume and Issue: 41(6), P. 836 - 851

Published: March 9, 2022

A series of symmetric and asymmetric tetraaminocyclopentadienone iron tricarbonyl complexes were prepared from Fe(CO)5 the diaminoacetylenes (DAA) R2NC≡CNR2 (NR2 = piperidinyl, 4-methylpiperidinyl, homopiperidinyl) via intermediate ferracyclobutenone complexes. In presence trimethylamine-N-oxide, reactions with acetonitrile afforded corresponding dicarbonyl complexes, which served as highly active precatalysts for transfer hydrogenation aldehydes, ketones, imines isopropanol hydrogen source aldehydes ketones dihydrogen under comparatively mild reaction conditions (3 bar H2 pressure, room temperature). Density functional theory (DFT) calculations performed to reveal mechanism isopropanol-mediated benzaldehyde acetophenone, is likely involve a catalytically hydroxycyclopentadienyl hydride species. Dihydrogen latter onto acetophenone occurs in concerted manner exceptionally low activation barriers following established outer-sphere mechanism.

Language: Английский

Borrowing Hydrogen for Organic Synthesis DOI Creative Commons

Benjamin G. Reed‐Berendt,

Daniel E. Latham,

Mubarak B. Dambatta

et al.

ACS Central Science, Journal Year: 2021, Volume and Issue: 7(4), P. 570 - 585

Published: March 25, 2021

Borrowing hydrogen is a process that used to diversify the synthetic utility of commodity alcohols. A catalyst first oxidizes an alcohol by removing form reactive carbonyl compound. This intermediate can undergo diverse range subsequent transformations before returns "borrowed" liberate product and regenerate catalyst. In this way, alcohols may be as alkylating agents whereby sole byproduct one-pot reaction water. recent decades, significant advances have been made in area, demonstrating many effective methods access valuable products. outlook highlights diversity metal biocatalysts are available for approach, well various performed, focusing on selection most advances. By succinctly describing conveying versatility borrowing chemistry, we anticipate its uptake will increase across wider scientific audience, expanding opportunities further development.

Language: Английский

Citations

324
Alcohols as Substrates in Transition-Metal-Catalyzed Arylation, Alkylation, and Related Reactions DOI

Adam Cook,

Stephen G. Newman

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(9), P. 6078 - 6144

Published: April 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

Language: Английский

Citations

40
Control of Absolute Stereochemistry in Transition‐Metal‐Catalysed Hydrogen‐Borrowing Reactions DOI Creative Commons
Timothy Kwok,

Oskar Hoff,

Roly J. Armstrong

et al.

Chemistry - A European Journal, Journal Year: 2020, Volume and Issue: 26(57), P. 12912 - 12926

Published: April 16, 2020

Abstract Hydrogen‐borrowing catalysis represents a powerful method for the alkylation of amine or enolate nucleophiles with non‐activated alcohols. This approach relies upon catalyst that can mediate strategic series redox events, enabling formation C−C and C−N bonds producing water as sole by‐product. In majority cases these reactions have been employed to target achiral racemic products. contrast, focus this Minireview is hydrogen‐borrowing‐catalysed in which absolute stereochemical outcome process be controlled. Asymmetric hydrogen‐borrowing rapidly emerging synthesis enantioenriched carbonyl containing products examples involving both bond are presented. A variety different approaches discussed including use chiral auxiliaries, asymmetric enantiospecific processes.

Language: Английский

Citations

102
Selective Catalytic Synthesis of α-Alkylated Ketones and β-Disubstituted Ketones via Acceptorless Dehydrogenative Cross-Coupling of Alcohols DOI

Dipanjan Bhattacharyya,

Bikash Kumar Sarmah,

Sekhar Nandi

et al.

Organic Letters, Journal Year: 2021, Volume and Issue: 23(3), P. 869 - 875

Published: Jan. 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.

Language: Английский

Citations

58
Divergent Synthesis of Alcohols and Ketones via Cross‐Coupling of Secondary Alcohols under Manganese Catalysis DOI

Feixiang Sun,

Jiamin Huang,

Zhihong Wei

et al.

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(26)

Published: April 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.

Language: Английский

Citations

32
Visible-light induced eosin Y catalysed C(sp2)-H alkylation of carbonyl substrates via direct HAT DOI
Satya P. Singh, Vishal Srivastava, Pravin K. Singh

et al.

Tetrahedron, Journal Year: 2023, Volume and Issue: 132, P. 133245 - 133245

Published: Jan. 5, 2023

Language: Английский

Citations

25
Single-Atom Fe-Catalyzed Acceptorless Dehydrogenative Coupling to Quinolines DOI

Yanze Lu,

Zhu Meiling,

Sanxia Chen

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(33), P. 23338 - 23347

Published: Aug. 6, 2024

A single-atom iron catalyst was found to exhibit exceptional reactivity in acceptorless dehydrogenative coupling for quinoline synthesis, outperforming known homogeneous and nanocatalyst systems. Detailed characterizations, including aberration-corrected HAADF-STEM, XANES, EXAFS, jointly confirmed the presence of atomically dispersed centers. Various functionalized quinolines were efficiently synthesized from different amino alcohols a range ketones or alcohols. The achieved turnover number (TON) up 10

Language: Английский

Citations

13
C-Alkylation of Various Carbonucleophiles with Secondary Alcohols under CoIII-Catalysis DOI
Priyanka Chakraborty, Nidhi Garg, Éric Manoury

et al.

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(14), P. 8023 - 8031

Published: June 26, 2020

Oxindoles have been successfully α-alkylated under Cp*CoIII catalysis by a vast array of secondary alcohols, including cyclic, acyclic, symmetrical, and unsymmetrical, to produce C-alkylated oxindoles. This protocol was also extended the α-alkylation N,N-dimethyl barbituric acid benzyl cyanides. The kinetic profile other preliminary mechanistic investigations suggest first-order reaction rate in oxindoles catalysts. A plausible catalytic cycle is proposed on basis profile, investigations, previous studies similar transformations, whereas density functional theory calculations provide insight into nature active species.

Language: Английский

Citations

55
Recent Advances for Alkylation of Ketones and Secondary Alcohols Using Alcohols in Homogeneous Catalysis DOI

Dongyuan Yang,

Hongli Wang, Chun‐Ran Chang

et al.

Advanced Synthesis & Catalysis, Journal Year: 2022, Volume and Issue: 364(18), P. 3100 - 3121

Published: July 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

Language: Английский

Citations

30
Iron(0)-Catalyzed Transfer Hydrogenative Condensation of Nitroarenes with Alcohols: A Straightforward Approach to Benzoxazoles, Benzothiazoles, and Benzimidazoles DOI

Ramachandra Reddy Putta,

Simin Chun, Seung Hyun Choi

et al.

The Journal of Organic Chemistry, Journal Year: 2020, Volume and Issue: 85(23), P. 15396 - 15405

Published: Nov. 2, 2020

The iron-catalyzed hydrogen transfer strategy has been applied to the redox condensation of o-hydroxynitrobenzene with alcohol, leading formation benzoxazole derivatives. A wide range 2-substituted benzoxazoles were synthesized in good excellent yields without addition an external agent. series control experiments provided a plausible mechanism. Furthermore, reaction system was successfully extended synthesis benzothiazoles and benzimidazoles.

Language: Английский

Citations

47