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Nicolai Cramer

Cette personne a quitté l’EPFL

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Publications associées (113)

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One-step access to N-enoxyimides by gold-catalysed addition of N-hydroxyimides to terminal alkynes

Nicolai Cramer, Coralie Danielle Annick Duchemin

N-Enoxyimides have become attractive substrates for novel catalytic transformations, yet their tedious multi-step synthesis hampers full exploitation of their synthetic potential. We report a gold(I)-catalyzed protocol to access N-enoxyimides from simple a ...

2019

One-Step Multigram-Scale Biomimetic Synthesis of Psiguadial B

Nicolai Cramer, Matthew Wodrich, Christopher Gordon Newton

A gram-scale synthesis of psiguadial B, a purported inhibitor of human hepatoma cell growth, has been achieved in one step by a biomimetic three-component coupling of caryophyllene, benzaldehyde, and diformylphloroglucinol. This cascade reaction is catalyz ...

Wiley-VCH Verlag GmbH2017

Chiral Cyclopentadienyl Ligands: Design, Syntheses, and Applications in Asymmetric Catalysis

Ana Garcia Herraiz, Nicolai Cramer, Benoît Daniel Bertrand Audic, Josep Más-Roselló, Aragorn Nathan Laverny

The creation of new chiral ligands capable of providing high stereocontrol in metal-catalyzed reactions is crucial in modern organic synthesis. The production of bioactive molecules as single enantiomers is increasingly required, and asymmetric catalysis w ...

Wiley-VCH Verlag GmbH2021

Efficient Kinetic Resolution of Sulfur-Stereogenic Sulfoximines by Exploiting (CpRhIII)-Rh-X-Catalyzed C-H Functionalization

Marcus Brauns, Nicolai Cramer

Chiral sulfoximines with stereogenic sulfur atoms are promising motifs in drug discovery. We report an efficient method to access chiral sulfoximines through a C-H functionalization based kinetic resolution. A rhodium(III) complex equipped with a chiral Cp ...

Wiley-VCH Verlag GmbH2019

Alkynyl Triazenes as Fluoroalkyne Surrogates: Regioselective Access to 4-Fluoro-2-pyridones by a Rh(III)-Catalyzed C–H Activation–Lossen Rearrangement–Wallach Reaction

Kay Severin, Nicolai Cramer, Carl Thomas Bormann, Jin Fay Tan

Fluorinated pyridones are an important scaffold displaying relevant biological activities. Efficient assembly strategies of pyridones are transition metal-catalyzed C–H annulations with alkynes. The inaccessibility and extreme lability of fluoro alkynes re ...

2020

Enantioselective Access to 1H-Isoindoles with Quaternary Stereogenic Centers by Palladium(0)-Catalyzed C-H Functionalization

Nicolai Cramer, Daria Grosheva

A catalytic enantioselective method for the synthesis of chiral 1H-isoindoles bearing quaternary stereogenic centers is reported. Powered by readily accessible phosphordiamidite ligands, the presented palladium(0)-catalyzed C-H function-alization uses trif ...

Wiley-VCH Verlag GmbH2018

Enantioselective Rhodium(I)-Catalyzed [3+2] Annulations of Aromatic Ketimines Induced by Directed C?H Activations

Nicolai Cramer

Triple selectivity: Highly substituted indenylamines can be obtained with high enantioselectivity by formal [3+2] additions of aryl ketimines with internal alkynes. These rhodium(I)-catalyzed processes proceed by selective C-H activation of one of the two ...

Wiley-VCH Verlag GmbH2011

Modular Chiral N-Heterocyclic Carbene Ligands for the Nickel-Catalyzed Enantioselective C-H Functionalization of Heterocycles

Nicolai Cramer, Johannes Diesel

N-Heterocyclic carbenes (NHCs) are the ligands of choice in a large variety of transformations entailing different transition metals. However, the number and variety of chiral NHCs suitable as stereo-controlling ligands in asymmetric catalysis remains limi ...

2020

Asymmetric Alkenyl C−H Functionalization by Cp x Rh III forms 2 H ‐Pyrrol‐2‐ones through [4+1]‐Annulation of Acryl Amides and Allenes

Nicolai Cramer, Shouguo Wang

An efficient CpxRhIII‐catalyzed enantioselective alkenyl C−H functionalization/[4+1] annulation of acryl amides and allenes is reported. The described transformation provides straightforward access to enantioenriched α,β‐unsaturated‐γ‐lactams bearing a qua ...

Wiley-VCH Verlag GmbH2019

Enantioselective palladium(0)-catalyzed C-H arylation strategy for chiral heterocycles

Nicolai Cramer, Tanguy Jean Daniel Saget

Transition-metal-catalyzed C-H functionalizations have emerged as complementary and powerful tools to access molecular complexity from widely available starting materials. Herein, we present a strategy for asymmetric intramolecular Pd(0)-catalyzed C-H func ...

De Gruyter2014

TADDOL-based phosphorus(III)-ligands in enantioselective Pd(0)-catalysed C-H functionalisations

Nicolai Cramer, Julia Pedroni

Monodentate TADDOL-derived phosphoramidites and phosphonites are versatile chiral ligands for enantio-selective Pd(0)-catalysed C-H functionalisations. They enable highly selective cyclisations to access a wide range of chiral carbo-and heterocycles. The h ...

Royal Society of Chemistry2015

Aromatic Homologation by Non- Chelate- Assisted RhIII- Catalyzed C -H Functionalization of Arenes with Alkynes

Nicolai Cramer, Van Manh Pham

Larger condensed arenes are of interest owing to their electro- and photochemical properties. An efficient synthesis is the catalyzed aromatic annulation of a smaller arene with two alkyne molecules. Besides difunctionalized starting materials, directed CH ...

Wiley-VCH Verlag GmbH2014

Total Synthesis of Fijiolide A

Nicolai Cramer, Christoph Heinz

Fijiolide A is a secondary metabolite isolated from a marine-derived actinomycete of the genus Nocardiopsis. It was found to significantly reduce the TNF-alpha induced activity of the transcription factor NF kappa B, which is considered a promising target ...

Schweizerische Chemische Gesellschaft2016

A Bulky Chiral N‐Heterocyclic Carbene Nickel Catalyst Enables Enantioselective C−H Functionalizations of Indoles and Pyrroles

Nicolai Cramer, Daria Grosheva, Johannes Diesel

An enantioselective nickel(0)-catalyzedC  Hfunc- tionalization of indoles and pyrroles that does not require the typical Lewis basic directing groups is disclosed. The reaction provides access to valuable tetrahydropyridoindoles and tetrahydroindolizines ...

Wiley-VCH Verlag GmbH2019

Rhodium(III)/Copper(II)-Promoted trans-Selective Heteroaryl Acyloxylation of Alkynes: Stereodefined Access to trans-Enol Esters

Nicolai Cramer, Van Manh Pham

Enol esters are versatile synthetic building blocks which can be elaborated by a wide variety of transformations. The classical synthesis by O-selective enolate acylation often hampers control of the E/Z selectivity with highly substituted substrates. A rh ...

Wiley-Blackwell2014

Chiral Cyclopentadienyl Iridium(III) Complexes Promote Enantioselective Cycloisomerizations Giving Fused Cyclopropanes

Nicolai Cramer, Yun-Suk Jang, Michael Christian Dieckmann

The cyclopentadienyl (Cp) group is a very important ligand for many transition-metal complexes which have been applied in catalysis. The availability of chiral cyclopentadienyl ligands (Cp-x) lags behind other ligand classes, thus hampering the investigati ...

Wiley-VCH Verlag GmbH2015

Enantioselective C-H Bond Functionalizations by 3d Transition-Metal Catalysts

Nicolai Cramer, Lukasz Piotr Wozniak

Direct catalytic modifications of carbon-hydrogen (C-H) bonds, ubiquitous in organic molecules, represent a powerful strategy in organic synthesis. In the past decade, chemists have focused on the development of sustainable methods for functionalization of ...

2019

Enantioselective Access to 3-Azabicyclo[3.1.0]hexanes by (CpRhIII)-Rh-x Catalyzed C-H Activation and Cp*Ir-III Transfer Hydrogenation

Ouidad Lahtigui, Nicolai Cramer, Coralie Danielle Annick Duchemin, Dan Forster

Rigid saturated nitrogen-containing scaffolds such as 3-azabicyclo[3.1.0]hexanes are very important and frequently occurring motifs in biologically active compounds. We disclose a flexible two-step protocol for their efficient and selective access. A tailo ...

AMER CHEMICAL SOC2022

Intermolecular Palladium(0)-Catalyzed Atropo-enantioselective C-H Arylation of Heteroarenes

Nicolai Cramer, Qui-Hien Nguyen

Atropisomeric (hetero)biaryls are motifs with increasing significance in ligands, natural products, and biologically active molecules. The straightforward construction of the stereogenic axis by efficient C-H functionalization methods is extremely rare and ...

2020

A Tunable Class of Chiral Cp Ligands for Enantioselective Rhodium(III)-Catalyzed C-H Allylations of Benzamides

Nicolai Cramer, Baihua Ye

The lack of robust and tunable chiral versions of cyclopentadienyl (Cp) ligands hampers progress in the development of catalytic asymmetric versions of a myriad of reactions catalyzed by this ubiquitous ligand. Herein, we describe of a class of chiral Cp l ...

Amer Chemical Soc2013