Nickel‐Catalyzed Asymmetric Hydrogenation of 2‐Amidoacrylates

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(13), P. 5371 - 5375

Published: Jan. 20, 2020

Earth-abundant nickel, coordinated with a suitable chiral bisphosphine ligand, was found to be an efficient catalyst for the asymmetric hydrogenation of 2-amidoacrylates, affording α-amino acid esters in quantitative yields and excellent enantioselectivity (up 96 % ee). The active component studied by NMR HRMS, which helped us realize high catalytic efficiency on gram scale low loading (S/C=2000). hydrogenated products could simply converted into acids, β-amino alcohols, their bioactive derivatives. Furthermore, mechanism investigated using deuterium-labeling experiments computational calculations.

Language: Английский

---

Chiral Phosphoric Acid Catalyzed Enantioselective Synthesis of α-Tertiary Amino Ketones from Sulfonium Ylides

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(33), P. 14384 - 14390

Published: July 22, 2020

Herein we disclose a new catalytic asymmetric approach for the synthesis of chiral α-amino ketones, which is particularly useful less accessible acyclic α-tertiary cases. By protonation–amination sequence, our represents rare H–heteroatom bond insertion by α-carbonyl sulfonium ylides, an attractive surrogate diazocarbonyls. The mild intermolecular C–N formation was catalyzed phosphoric acids with excellent efficiency and enantioselectivity. products are precursors to other important amine derivatives, including drug molecules ligands. enantioselectivity controlled dynamic kinetic resolution in amination step, rather than initial protonation. This process opens up platform development related reactions.

Language: Английский

---

Asymmetric transformations from sulfoxonium ylides

Chemical Science, Journal Year: 2021, Volume and Issue: 13(5), P. 1192 - 1209

Published: Dec. 8, 2021

Sulfoxonium ylides are important surrogates for diazo compounds, and their use in industry as safer alternatives has been evaluated during recent years. Beyond the known classical transformations, these have also used a surprising plethora of novel intrinsic chemical reactions, especially Bench stability handling an advantage this class organosulfur molecules. Despite this, efficient asymmetric specifically catalytic enantioselective versions, only recently reported, there specific reasons this. This perspective article covers topic from first studies up to latest advances, giving personal perspectives showing main challenges area coming

Language: Английский

---

Asymmetric Intramolecular Dearomatization of Nonactivated Arenes with Ynamides for Rapid Assembly of Fused Ring System under Silver Catalysis

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 143(2), P. 604 - 611

Published: Dec. 31, 2020

Arene dearomatization is a straightforward method for converting an aromatic feedstock into functionalized carbocycles. Enantioselective dearomatizations of chemically inert arenes, however, are quite limited and underexplored relative to those phenols indoles. We developed diazo-free generation silver-carbene species from ynamide applied it the nonactivated arenes. Transiently generated norcaradiene could be trapped by intermolecular [4 + 2] cycloaddition, synthesizing polycycles with five consecutive stereogenic centers. This protocol constitutes first highly enantioselective reaction based on species. Mechanistic investigations revealed followed two different classes pericyclic reactions, as well origin chemo- enantioselectivity.

Language: Английский

---

Site-Selective C–H Benzylation of Alkanes with N-Triftosylhydrazones Leading to Alkyl Aromatics

Chem, Journal Year: 2020, Volume and Issue: 6(8), P. 2110 - 2124

Published: July 23, 2020

Language: Английский

---

Propargylic Amination Enabled the Access to Enantioenriched Acyclic α-Quaternary α-Amino Ketones

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(20), P. 7629 - 7634

Published: May 14, 2021

A propargylic amination approach toward chiral acyclic α-quaternary α-amino ketones is described. This Cu-catalyzed procedure could be performed open to air using commercially available amines as nucleophiles. The key success the use of rationally designed cyclic carbonates substrates, which can generate a Cu-bonded enolate zwitterionic intermediate upon decarboxylation. protocol features wide functional group tolerance and high asymmetric induction, with typical ee value higher than 93%, thus advances great step forward in challenging synthesis ketones.

Language: Английский

---

Dual-function enzyme catalysis for enantioselective carbon–nitrogen bond formation

Nature Chemistry, Journal Year: 2021, Volume and Issue: 13(12), P. 1166 - 1172

Published: Oct. 18, 2021

Language: Английский

---

Site-Selective α-C–H Functionalization of Trialkylamines via Reversible Hydrogen Atom Transfer Catalysis

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(45), P. 18952 - 18959

Published: Nov. 5, 2021

Trialkylamines are widely found in naturally occurring alkaloids, synthetic agrochemicals, biological probes, and especially pharmaceuticals agents preclinical candidates. Despite the recent breakthrough of catalytic alkylation dialkylamines, selective α-C(sp3)–H bond functionalization available trialkylamine scaffolds holds promise to streamline complex synthesis, accelerate drug discovery, execute late-stage pharmaceutical modification with complementary reactivity. However, canonical methods always result at less-crowded site. Herein, we describe a solution switch reaction site through fundamentally overcoming steric control that dominates such processes. By rapidly establishing an equilibrium between α-amino C(sp3)–H bonds highly electrophilic thiol radical via reversible hydrogen atom transfer, leverage slower radical-trapping step electron-deficient olefins selectively forge C(sp3)–C(sp3) more-crowded radical, overall selectivity guided by Curtin–Hammett principle. This subtle profile has unlocked new strategic concept direct C–H arena for forging C–C from diverse set trialkylamines high levels preparative utility. Simple correlation 13C NMR shift serves as qualitative predictive guide. The broad consequences this dynamic system, together ability N-substituted quaternary carbon centers implement techniques, hold potential synthesis small-molecule discovery.

Language: Английский

---

Highly Atroposelective Rhodium(II)-Catalyzed N–H Bond Insertion: Access to Axially Chiral N-Arylindolocarbazoles

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(10), P. 6135 - 6140

Published: May 6, 2021

The highly atroposelective construction of axially chiral N-arylindolocarbazoles is disclosed via the Rh(II)-catalyzed intermolecular carbene N–H insertion reactions. This straightforward transformation provides a rapid access to wide range enantio-enriched N-arylindolocarbazole atropisomers bearing C–N axis in moderate good yields and high enantioselectivities. Also, synthetic utility this protocol unambiguously emphasized by late-stage functionalization (LSF) some representative natural products bioactive molecules. Furthermore, polyaromatic ring N-arylindolocarbazole-derived phosphoric acid (CPA) synthesis also highlight its practical value materials chemistry catalytic asymmetric synthesis.

Language: Английский

---

Site-selective amination towards tertiary aliphatic allylamines

Nature Catalysis, Journal Year: 2022, Volume and Issue: 5(7), P. 642 - 651

Published: July 22, 2022

Language: Английский

---