Diamidophosphites from β-hydroxyamides: readily assembled ligands for Pd-catalyzed asymmetric allylic substitution DOI
Ilya V. Chuchelkin, Konstantin N. Gavrilov, Nataliya E. Borisova

et al.

Dalton Transactions, Journal Year: 2020, Volume and Issue: 49(17), P. 5625 - 5635

Published: Jan. 1, 2020

Two groups of modular chiral diamidophosphite ligands were easily synthesised from accessible N-Boc-amino alcohols and pseudodipeptides. The reaction these compounds with [Pd(allyl)Cl]2 in the presence AgBF4 yielded complexes [Pd(allyl)(L)2]BF4. In addition, metallochelates [Pd(allyl)(L)]BF4 (S)-methioninol-based P,S-bidentate prepared. structures novel elucidated by means 2D-NMR confirmed single-crystal X-ray diffraction, as well DFT calculations. Asymmetric inducers this type exhibited high enantioselectivities Pd-mediated allylic substitution (E)-1,3-diphenylallyl ethyl carbonate CH2(CO2Me)2 (up to 98% ee) (CH2)4NH 92% ee). Ee values up 86% 73% obtained Pd-catalyzed alkylation cinnamyl acetate 2-oxocyclohexane-1-carboxylate 2-oxocyclopentane-1-carboxylate, respectively. effects structural modules, such nature phosphorus-containing ring or exocyclic substituent, on catalytic activity enantioselectivity investigated.

Language: Английский

Enantioselective Intramolecular Allylic Substitution via Synergistic Palladium/Chiral Phosphoric Acid Catalysis: Insight into Stereoinduction through Statistical Modeling DOI
Cheng‐Che Tsai, Christopher Sandford, Tao Wu

et al.

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(34), P. 14647 - 14655

Published: May 26, 2020

The mode of asymmetric induction in an enantioselective intramolecular allylic substitution reaction catalyzed by a combination palladium and chiral phosphoric acid was investigated combined experimental statistical modeling approach. Experiments to probe nonlinear effects, the reactivity deuterium-labeled substrates, control experiments revealed that nucleophilic attack π-allylpalladium intermediate is enantio-determining step, which phosphate anion involved stereoinduction. Using multivariable linear regression analysis, we determined multiple noncovalent interactions with environment are integral enantiocontrol transition state. synthetic protocol form pyrrolidines further applied construction C-O bonds at fully substituted carbon centers synthesis 2,2-disubstituted benzomorpholines.

Language: Английский

Citations

41
Photoinduced Electron Donor Acceptor Complex‐Enabled α‐C(sp3)−H Alkenylation of Amines DOI

Jianzhong Lu,

Kaiyao Yuan,

Jia-Lian Zheng

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(44)

Published: July 13, 2024

Allylic amines are prevalent and vital structural components present in many bioactive compounds natural products. Additionally, they serve as valuable intermediates building blocks, with wide-ranging applications organic synthesis. However, direct α-C(sp

Language: Английский

Citations

5
Asymmetric Allylic Alkylation of β-Ketoesters via C–N Bond Cleavage of N-Allyl-N-methylaniline Derivatives Catalyzed by a Nickel–Diphosphine System DOI
Haruki Nagae,

Jingzhao Xia,

Evgueni Kirillov

et al.

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(10), P. 5828 - 5839

Published: April 22, 2020

Nickel complexes bearing chiral diphosphine ligands, such as (S)-Tol-MeO-BIPHEP and (S)-H8-BINAP, serve efficient catalysts for asymmetric allylic alkylation (AAA) of β-ketoesters, using amines allyl sources. The reactions proceed with high catalytic activity enantioselectivity. N-Methyl-N-phenyl were indispensable to achieve the activity, enantioselectivity, expand substrate scope 5- 7-membered whose nickel-catalyzed AAA alcohols results in low On basis kinetics a catalyst system made Ni(cod)2 (S)-Tol-MeO-BIPHEP, DFT calculations reaction pathway mediated by an isolated olefin-coordinated nickel–DPPF complex 4b, we propose mechanism where protonation nitrogen atom coordinating amine β-ketoester is key cleaving C–N bond delivering cationic π-allyl nickel(II) intermediate.

Language: Английский

Citations

39
Highly Efficient and Selective N-Alkylation of Amines with Alcohols Catalyzed by in Situ Rehydrated Titanium Hydroxide DOI
Feng Niu, Qiyan Wang, Zhen Yan

et al.

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(5), P. 3404 - 3414

Published: Feb. 11, 2020

Catalytic N-alkylation of amines by alcohols to produce desired is an important catalytic reaction in industry. Various noble-metal-based homogeneous and heterogeneous catalysts have been reported for this process. The development cheap non-noble-metal the would be highly desirable. Hereby, we propose over a efficient catalyst—titanium hydroxide. This catalyst provides selectivity higher than 90% secondary functionalized aromatic aliphatic with high activity stability. Mild Brönsted acidity formed continuous rehydration Lewis excludes side reactions deactivation adsorbed species. mechanism involves dehydration ethers subsequent C–O bond cleavage amine formation recovery alcohol.

Language: Английский

Citations

30
Sustainable Palladium-Catalyzed Tsuji–Trost Reactions Enabled by Aqueous Micellar Catalysis DOI

Nicholas R. Lee,

Farbod A. Moghadam, Felipe C. Braga

et al.

Organic Letters, Journal Year: 2020, Volume and Issue: 22(13), P. 4949 - 4954

Published: June 18, 2020

Palladium-catalyzed allylic substitution, or "Tsuji-Trost" reactions, can be run under micellar catalysis conditions featuring not only chemistry in water but also numerous combinations of reaction partners that require low levels palladium, typically on the order 1000 ppm (0.1 mol %). These couplings are further characterized by especially mild conditions, leading to a number cases previously reported an aqueous medium. Inclusion diverse nucleophiles, such as N-H heterocycles, alcohols, dicarbonyl compounds, and sulfonamides is described. Intramolecular cyclizations illustrate broad utility this process. In addition recycling studies, multigram scale example reported, indicative prospects for up.

Language: Английский

Citations

28
Access to 3‐Oxindoles from Allylic Alcohols and Indoles DOI
Hortense Lauwick, Yang Sun, H. Akdas

et al.

Chemistry - A European Journal, Journal Year: 2018, Volume and Issue: 24(31), P. 7964 - 7969

Published: March 15, 2018

Abstract The site‐selective and regioselective allylation of 2‐substituted indoles was performed by using a ruthenium(IV) precatalyst containing phosphine–sulfonate chelate. Mono‐, di‐, triallylated were selectively obtained depending on the reaction conditions with formation water as only byproduct. preparation 3‐oxindole derivatives then successfully owing to air oxidation corresponding allylated indoles. Diallylated pseudoindoxyls proven be good synthons perform cyclization through ring‐closing metathesis afford tricyclic adducts. photophysical properties 3‐oxindoles measured, some compounds showed strong fluorescence in water.

Language: Английский

Citations

31
Domino Synthesis of α,β‐Unsaturated γ‐Lactams by Stereoselective Amination of α‐Tertiary Allylic Alcohols DOI
Jianing Xie,

Sijing Xue,

Eduardo C. Escudero‐Adán

et al.

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(51), P. 16727 - 16731

Published: Oct. 29, 2018

Tertiary allylic alcohols equipped with a carboxyl group can be smoothly aminated under ambient conditions by conceptually new and stereoselective protocol palladium catalysis. The in situ formed Z-configured γ-amino acid cyclizes to afford an α,β-unsaturated γ-lactam, releasing water as the only byproduct. This practical catalytic transformation highlights use of acting activating stereodirecting functional provide wide series pharma-relevant building blocks. Various control reactions support crucial role substrate mediate these transformations.

Language: Английский

Citations

28
The Hancock Alkaloids Angustureine, Cuspareine, Galipinine, and Galipeine: A Review of their Isolation, Synthesis, and Spectroscopic Data DOI

Stephen G. Davies,

Ai M. Fletcher,

Paul M. Roberts

et al.

European Journal of Organic Chemistry, Journal Year: 2019, Volume and Issue: 2019(31-32), P. 5093 - 5119

Published: June 25, 2019

A review of the isolation, reported methods for synthesis (up to end 2018), and spectroscopic data angustureine, cuspareine, galipinine, galipeine, members Hancock family alkaloids based upon a 2‐substituted N(1)‐methyl‐1,2–3,4‐tetrahydroisolquinoline scaffold, is presented.

Language: Английский

Citations

27
A color-tunable single-benzene fluorophore-based sensor for sensitive detection of palladium in solution and living cells DOI Creative Commons
Paulína Takácsová, Marie Pešková, P Svec

et al.

The Analyst, Journal Year: 2023, Volume and Issue: 148(9), P. 2058 - 2063

Published: Jan. 1, 2023

Single-benzene fluorophores are bright and the smallest fluorochromes known so far. In single-benzene fluorophores, fluorescence is mediated by push/pull effect of substituting groups. Despite a plethora advantageous properties, this group molecules has not been extensively studied for design high-performance fluorescent sensors catalytic or enzymatic activities. Thus, herein, new probes based on Tsuji-Trost reaction were developed selective detection palladium other transition metals (platinum gold) in an aqueous/organic mixed solvent with sensitivity down to 2.5 nM (for palladium). The relative flexibility synthesis these allows facile color tuning emitted fluorescence. study, we have successfully utilized yellow emission variant sensitive under cell-free conditions living cells, validating its possible applicability high-throughput optical sensing catalysts bioorthogonal chemistry physiological conditions.

Language: Английский

Citations

9
Enzymatic N-Allylation of Primary and Secondary Amines Using Renewable Cinnamic Acids Enabled by Bacterial Reductive Aminases DOI Creative Commons
Godwin A. Aleku, Gabriel R. Titchiner,

George Roberts

et al.

ACS Sustainable Chemistry & Engineering, Journal Year: 2022, Volume and Issue: 10(20), P. 6794 - 6806

Published: May 6, 2022

Allylic amines are a versatile class of synthetic precursors many valuable nitrogen-containing organic compounds, including pharmaceuticals. Enzymatic allylic amination methods provide sustainable route to these compounds but often restricted primary amines. We report biocatalytic system for the reductive

Language: Английский

Citations

14