Copper-catalyzed syn-hydroformylation of alkynes with silane and N,N-dimethylformamide dimethylacetal DOI

Menglin Huai,

Long Chen, Wei Dong

et al.

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(26), P. 5385 - 5392

Published: Jan. 1, 2024

A copper-catalyzed

Language: Английский

Site-Selective Copper(I)-Catalyzed Hydrogenation of Amides DOI Creative Commons
Dimitrios‐Ioannis Tzaras,

Mahadeb Gorai,

Thomas Jacquemin

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 3, 2025

We present a bifunctional catalyst consisting of copper(I)/N-heterocyclic carbene and an organocatalytic guanidine moiety that enables, for the first time, copper(I)-catalyzed reduction amides with H2 as terminal reducing agent. The allows reactivity tuning originally weakly nucleophilic copper(I) hydrides – formed in situ to be able react difficult-to-reduce amides. Additionally, is key selective recognition "privileged" based on simple readily available heterocycles presence other within one molecule, giving rise hitherto unknown site-selective catalytic amide hydrogenation. A substrate scope, mechanistic investigations, working hypothesis supported by computational analysis site-selectivity are presented.

Language: Английский

Citations

4
Broadly Applicable Copper(I)-Catalyzed Alkyne Semihydrogenation and Hydrogenation of α,β-Unsaturated Amides Enabled by Bifunctional Iminopyridine Ligands DOI Creative Commons

Mahadeb Gorai,

J. Franzen,

Philipp Rotering

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: April 16, 2025

A highly active bifunctional catalyst consisting of a copper(I)/N-heterocyclic carbene complex and basic 2-iminopyridine subunit allows for copper hydride chemistry under low H2 pressure, achieving efficient catalysis reaching 1 bar (balloon pressure). The tolerates remarkable variety functional groups in catalytic alkyne semihydrogenations. Furthermore, this design gives rise to high reactivity that the hydrogenation α,β-unsaturated amides (a substrate class hitherto unreactive catalysis) at pressure first time. In manner, late-stage modification isotope labeling amides, common subunits biologically compounds, can be realized through using first-row transition metal based on abundant copper. Preliminary mechanistic experiments indicate operates via an iminopyridine-mediated proximity effect. We hypothesize coordination alcohol as proton source copper(I) facilitates overall reactions rapid proto-decupration step.

Language: Английский

Citations

1
Synthesis of a Library of Bifunctional N‐Heterocyclic Carbene Ligand Precursors with Hydrogen Bond Donor Subunits DOI
Dimitrios‐Ioannis Tzaras,

Maximilian Voigtländer,

Birte Zimmermann

et al.

European Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: May 13, 2025

Bifunctional N‐heterocyclic carbenes (NHCs) with additional hydrogen bond donor groups in the backbone are important organocatalysts and ligands for transition metal complexes. Herein, a straightforward synthetic approach to library of bifunctional imidazolium salts, precursors respective NHCs amidine, squaramide, (thio)urea moieties as donors, is reported. The preparation palladium(II) copper(I) NHC complexes their application catalysis presented.

Language: Английский

Citations

0
(Semi)hydrogenation of enoates and alkynes effected by a versatile, particulate copper catalyst DOI Creative Commons
Samuel Redl, Christoph Topf

Tetrahedron Chem, Journal Year: 2024, Volume and Issue: 12, P. 100089 - 100089

Published: Aug. 15, 2024

We communicate a versatile and user-friendly Cu-based catalytic method that allows for the selective hydrogenation of enoates alkynes. The introduced protocol is free from any ex ante modifications used Cu(I) precursors by air-sensitive phosphines or elaborate N-heterocyclic carbene ligands. conjugate (selective) reduction CC bonds achieved through [Cu(CH3CN)4]+/tert-butoxide pair whereby we describe delicate influence base cation on chemoselectivity respective transformation. In case ester-to-alcohol reduction, combination simple CuI NaOtBu proved to be successful. Deuteration experiments are included address certain mechanistic aspects system. All requisite chemicals readily obtainable commercial channels catalyst assembly set up bench without need special lab-technical precautions.Graphical abstract

Language: Английский

Citations

2
BINAP-CuH-catalysed enantioselective allylation using alkoxyallenes to access 1,2-syn-tert,sec-diols DOI Creative Commons

N. Navaneetha,

Sundaram Maurya, Prativa Behera

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

An economical method for highly enantioselective and diastereoselective synthesis of 1,2- syn-tert , sec -diols via Cu-BINAP-catalysed reductive coupling alkoxyallenes with ketones.

Language: Английский

Citations

2
A ligand-assisted proximity effect allows for H2-driven copper hy-dride chemistry under mild conditions DOI Creative Commons

Mahadeb Gorai,

Philipp Rotering,

J. Franzen

et al.

Published: Oct. 16, 2024

A bifunctional copper(I)/N-heterocyclic carbene complex bearing a highly basic 2-iminopyridine subunit effects variety of copper(I) hydride-based reductive transformations at low H2 pressure. The catalyst allows for the first time to employ only catalytic amounts alkoxide additive and is with highest reactivity towards re-ported so far. We can demonstrate that efficient alkyne semihydrogenations, conjugate reductions as well 1,2-reductions carbonyl compounds be carried out very new protocol circumvents need previously required high-pressure equipment. At same time, use iminopyridine-based ligand tolerance an unprecedented functional groups in realm copper(I)-catalyzed hydrogenations. possible working model featuring iminopyridine-mediated proximity effect coordinates key close reactive cop-per(I) center proposed account observed significant rise reactivity. Mechanistic studies directed support-ing this current hypothesis are presented.

Language: Английский

Citations

1
Chiral Bifunctional NHC–Guanidine Ligands for Asymmetric Hydrogenation DOI
Johannes F. Teichert,

Mahadeb Gorai

Synlett, Journal Year: 2023, Volume and Issue: 35(09), P. 989 - 992

Published: Dec. 14, 2023

Abstract We report the synthesis of chiral N-heterocyclic carbene/guanidine bifunctional ligands from readily available amino alcohols. The resulting copper(I) complexes are active catalysts in an asymmetric hydrogenation ketones. show that linker unit can be employed for transfer stereoinformation.

Language: Английский

Citations

3
(Semi)Hydrogenation of Enoates and Alkynes Effected by a Versatile, Particulate Copper Catalyst DOI
Samuel Redl, Christoph Topf

Published: Jan. 1, 2024

SUMMARYWe communicate a versatile and user-friendly Cu-based catalytic method that allows for the selective hydrogenation of enoates alkynes. The introduced protocol is free from any ex ante modifications used Cu(I) precursors by air-sensitive phosphines or elaborate N-heterocyclic carbene ligands. conjugate (selective) reduction C≡C bonds achieved through [Cu(CH3CN)4]+/tert-butoxide pair whereby we describe delicate influence base cation on chemoselectivity respective transformation. In case ester-to-alcohol reduction, combination simple CuI NaOtBu proved to be successful. Deuteration experiments are included address certain mechanistic aspects system. All requisite chemicals readily obtainable commercial channels catalyst assembly set up bench without need special lab-technical precautions.

Language: Английский

Citations

0
Copper-catalyzed syn-hydroformylation of alkynes with silane and N,N-dimethylformamide dimethylacetal DOI

Menglin Huai,

Long Chen, Wei Dong

et al.

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(26), P. 5385 - 5392

Published: Jan. 1, 2024

A copper-catalyzed

Language: Английский

Citations

0