Publications associées à Auxiliaire chiral

Catalytic Enantioselective Synthesis of Inherently Chiral Macrocycles by Dynamic Kinetic Resolution

Kinetically fast racemization of chiral substrates through an achiral intermediate and enantioselective functionalization of one of the enantiomeric substrates forms the basis of the dynamic kinetic resolution (DKR) of centrally chiral molecules. We report ...

2024

Chalcogen bonding catalysis

Jieping Zhu

Catalysts play a major role in chemical synthesis, and catalysis is considered to be a green and economic process. Catalysis is dominated by covalent interactions between the catalyst and substrate. The design of non-covalent catalysts came into limelight ...

Royal Society of Chemistry2024

Chemodivergent Asymmetric Synthesis via Catalytically Formed Chiral Auxiliary

Mikus Purins

In summary, the development of the catalytically formed chiral auxiliary concept is described. In this approach, an oxazolidine auxiliary is installed via enantioselective Pd catalysis from readily available starting materials in an enantioselective tether ...

EPFL2023

Copper (I)‐BOX Catalyzed Asymmetric 3‐Component Reaction for the Synthesis of Trifluoromethylated Propargylic Ethers and Anilines**

Jérôme Waser, Nieves Pilar Ramirez Hernandez

An asymmetric 3-component reaction between EthynylBenziodoXoles (EBXs), 2,2,2-trifluorodiazoethane and nucleophiles catalyzed by a CuI-BOX (Bisoxazoline) catalyst is described. This protocol gives access to chiral trifluoromethylated propargyl ethers and a ...

Wiley-VCH Verlag GmbH2023

Enantioselective Total Synthesis of (+)-Stephadiamine

Qian Wang, Jieping Zhu, Baochao Yang, Guang Li

An asymmetric synthesis of (+)-stephadiamine has been accomplished featuring (a) an enantioselective dearomatizative Michael addition to generate a quaternary stereocenter; (b) a domino sequence involving reductive generation of nitrone from γ-nitro ketone ...

2023

Asymmetric Construction of α,α‐Disubstituted Piperazinones Enabled by Benzilic Amide Rearrangement

Jieping Zhu, Hua Wu, Yuping He

An unprecedent asymmetric catalytic benzilic amide rearrangement for the synthesis of α,α-disubstituted piperazinones is reported. The reaction proceeds via a domino [4+1] imidazolidination/formal 1,2-nitro- gen shift/1,2-aryl or alkyl migration sequence, ...

Wiley-VCH Verlag GmbH2023

Tandem Hydroformylation-Aldol Condensation Reaction Enabled by Zn-MOF-74

Berend Smit, Daniele Ongari

The tandem hydroformylation-aldol condensation (tandem HF-AC) reaction offers an efficient synthetic route to the synthesis of industrially relevant products. The addition of Zn-MOF-74 to the cobalt-catalyzed hydroformylation of 1-hexene enables tandem HF- ...

WILEY-V C H VERLAG GMBH2023

Synthesis and Applications of Ynimines and Enantioselective Total Synthesis of Artatrovirenol A

Rémi Hugo Lavernhe

The first chapter of this thesis describe the development of a general synthesis of ynimines, an under-exploited motif in organic chemistry. In the presence of an inexpensive copper catalyst and 2,2'-biquinoline, reaction of easily accessible O-acyloximes ...

EPFL2023

Enantio- and diastereoselective construction of vicinal C(sp(3)) centres via nickel-catalysed hydroalkylation of alkenes

Xile Hu, Chao Fan, Srikrishna Bera

In drug discovery, the proportion of aliphatic carbons (C(sp(3))) and the presence of chiral carbons in organic molecules are positively correlated to their chance of clinical success. Although methods exist for the synthesis of chiral C(sp(3))-rich molecu ...

2022

Asymmetric Cyclopropanation and Epoxidation via a Catalytically Formed Chiral Auxiliary

Jérôme Waser, Mikus Purins

For the enantioselective diversification of a single starting material, a different chiral catalyst is usually required for each transformation. Herein, we extend the concept of catalytically formed chiral auxiliary from hydrogenation to the asymmetric cyc ...

Wiley-VCH Verlag GmbH2022

Visible light activated BINOL-derived chiroptical switches based on boron integrated hydrazone complexes

Lukas Pfeifer

Chiral optical switches, which use light to control chirality in a reversible manner, offer unique properties and fascinating prospects in the areas of molecular switching and responsive systems, new photochromic materials and molecular data processing and ...

ROYAL SOC CHEMISTRY2022

Conformal and chiral phase transitions in Rydberg chains

Frédéric Mila, Natalia Chepiga, Ivo Aguiar Maceira

Using density matrix renormalization group simulations on open chains, we map out the wave vector in the incommensurate disordered phase of a realistic model of Rydberg chains with 1/r6 interactions, and we locate and characterize the points along the comm ...

AMER PHYSICAL SOC2022

(4+3) Annulation of Donor-Acceptor Cyclopropanes and Azadienes: Highly Stereoselective Synthesis of Azepanones

Jérôme Waser, Stefano Nicolai

Azepanes are important seven-membered heterocycles, which are present in numerous natural and synthetic compounds. However, the development of convergent synthetic methods to access them remains challenging. Herein, we report the Lewis acid catalyzed (4+3) ...

Wiley-VCH Verlag GmbH2022

Palladium-Catalyzed trans-Hydroalkoxylation: Counterintuitive Use of an Aryl Iodide Additive to Promote C-H Bond Formation

Jérôme Waser, Mikus Purins, Ashis Kumar Das, Luca Buzzetti

We report an enantioselective palladium-catalyzed trans-hydroalkoxylation of propargylic amines with a trifluoroacetaldehydederived tether to build chiral oxazolidines. Diastereoselective hydrogenation using a heterogeneous palladium catalyst then gave acc ...

2022

Chiral Alkyl Amine Synthesis via Catalytic Enantioselective Hydroalkylation of Enecarbamates

Xile Hu, Srikrishna Bera, Deyun Qian

Chiral alkyl amines are omnipresent as bioactive molecules and synthetic intermediates. The catalytic and enantioselective synthesis of alkyl amines from readily accessible precursors is challenging. Here we develop a nickel-catalyzed hydroalkylation metho ...

AMER CHEMICAL SOC2021

Visible-Light-Driven Catalytic Deracemization of Secondary Alcohols

Xile Hu, Zhikun Zhang

Deracemization of racemic chiral compounds is an attractive approach in asymmetric synthesis, but its development has been hindered by energetic and kinetic challenges. Here we describe a catalytic deracemization method for secondary benzylic alcohols whic ...

Wiley-VCH Verlag GmbH2021

Kibble-Zurek exponent and chiral transition of the period-4 phase of Rydberg chains

Frédéric Mila, Natalia Chepiga

Chains of Rydberg atoms have emerged as an amazing playground to study quantum physics in 1D. Playing with inter-atomic distances and laser detuning, one can in particular explore the commensurate-incommensurate transition out of density waves through the ...

Nature Research2021

Schiff base ligands derived from 1,2-bis(2 '-nitro-/amino-phenoxy)-3-R-benzene and 2-hydroxy-1-naphthaldehyde and their Cu/Zn(II) complexes: synthesis, characterization, X-ray structures and computational studies

Rosario Scopelliti

1,2-Bis(2'-nitrophenoxy)-3-R-benzenes {R = H (1), CH3 (2) and OCH3 (3)} have been prepared from the S-N-Ar reaction between 1-fluoro-2-nitrobenzene and 3-R-catechol (aromatic diol), and are then reduced to the corresponding diamines 1,2-bis(2'-aminophenoxy ...

ROYAL SOC CHEMISTRY2021

Enantioselective Carboetherification/Hydrogenation for the Synthesis of Amino Alcohols via a Catalytically Formed Chiral Auxiliary

Jérôme Waser, Mikus Purins, Phillip Gulliver Dominic Greenwood, Luca Buzzetti

Chiral auxiliaries and asymmetric catalysis are the workhorses of enantioselective transformations, but they still remain limited in terms of either efficiency or generality. Herein, we present an alternative strategy for controlling the stereoselectivity ...

2020

Rhodium(III)-Catalyzed Cyclopropane C-H/C-C Activation Sequence Provides Diastereoselective Access to alpha-Alkoxylated gamma-Lactams

Nicolai Cramer, Benoît Daniel Bertrand Audic

A Cp*Rh(III)-catalyzed C-H/C-C bond activation sequence of cyclopropyl hydroxamates has been developed. The three-component process allows trapping of the intermediate rhodacycle with diazomalonates and an alcohol nucleophile to provide access to synthetic ...

AMER CHEMICAL SOC2020