Publications associées à Cyclopropanation

Photocatalyzed [2σ + 2σ] and [2σ + 2π] Cycloadditions for the Synthesis of Bicyclo[3.1.1]heptanes and 5- or 6-Membered Carbocycles

Jérôme Waser, Matthew Wodrich, André Bossonnet

We report the use of photocatalysis for the homolytic ring-opening of carbonyl cyclopropanes. In contrast to previous studies, our approach does not require a metal cocatalyst or a strong reductant. The carbonyl cyclopropanes can be employed for both [2σ + ...

2023

Ring-Opening Reactions of Aminocyclopropanes and Aminocyclobutanes

Mingming Wang

Nitrogen-containing compounds are an important class of molecules in medicinal chemistry, chemical biology, biochemistry, material sciences or environmental sciences. Organic nitrogen occurs in many forms, ranging from small building blocks such as urea, a ...

EPFL2022

Mapping Catalyst‐Solvent Interplay in Competing Carboamination/Cyclopropanation Reactions

Nicolai Cramer, Matthew Wodrich, Anne-Clémence Corminboeuf, Miyeon Chang, Simone Gallarati

Group 9 metals, in particular Rh III complexes with cyclopentadienyl ligands, are competent C–H activation catalysts. Recently, a Cp*Rh III catalyzed reaction of alkenes with N -enoxyphthalimides showed divergent outcome based on the solvent, with carboami ...

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

Nitrous oxide as a diazo transfer reagent: the synthesis of triazolopyridines

Kay Severin, Farzaneh Fadaei Tirani, Iris Roswitha Landman

Nitrous oxide is a potential diazo transfer reagent, but its applications in organic chemistry are scarce. Here, we show that triazolopyridines and triazoloquinolines are formed in the reactions of metallated 2-alkylpyridines or 2-alkylquinolines with N2O. ...

Royal Society of Chemistry2021

Isolation and characterization of diazoolefins

Rosario Scopelliti, Kay Severin, Farzaneh Fadaei Tirani, Zhaowen Dong, Paul Varava

Diazoolefins tend to be highly reactive compounds that rapidly lose dinitrogen. So far, most experimental evidence for diazoolefins is indirect, via trapping experiments. Here we show that diazoolefins are observed to form in reactions of N-heterocyclic ol ...

2021

Colloidal Synthesis of Cu-M-S (M = V, Cr, Mn) Nanocrystals by Tuning the Copper Precursor Reactivity

Raffaella Buonsanti, Seyedehbehnaz Varandili, Valeria Mantella, James Richard Pankhurst

New ternary and higher order inorganic materials are needed for a large variety of applications, yet their synthesis still represents a chemistry challenge. Herein, we focus on the synthesis of Cu-M-S nanocrystals (where M = V, Cr, Mn) via a wet-chemistry ...

2020

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

Chiral N-Heterocyclic Carbene Ligands for Asymmetric Catalysis

Johannes Diesel

N-Heterocyclic carbenes (NHCs) are the ligands of choice in a large variety of transformations entailing different transition metals. However, the number of chiral NHCs suitable as stereocontrolling ligands in asymmetric catalysis remains limited. In parti ...

EPFL2019

Divergent Reactivity of Thioalkynes in Lewis Acid Catalyzed Annulations with Donor-Acceptor Cyclopropanes

Rosario Scopelliti, Jérôme Waser, Sophie Lucie Racine, Bence Márton Hegedüs

Efficient methods for the convergent synthesis of (poly) cyclic scaffolds are urgently needed in synthetic and medicinal chemistry. Herein, we describe new annulation reactions of thioalkynes with phthalimide-substituted donor-acceptor cyclopropanes, which ...

Wiley-Blackwell2016

Synthetic studies towards Lundurines A-C

Michele Boghi

Recent advances in transition metal catalyzed C-H activation are revolutionizing synthetic organic chemistry, and application of this powerful synthetic tool in the context of total synthesis of complex natural products is beginning to blossom. This thesis ...

EPFL2015

Cyclization and annulation reactions of nitrogen-substituted cyclopropanes and cyclobutanes

Jérôme Waser, Reto Frei, Fides Benfatti, Florian Patrick Marie Daniel De la Barre De Nanteuil, Filippo De Simone, Eloísa Sofía Serrano Robledo

Cyclization and annulation reactions initiated by ring-opening of small rings, especially cyclopropanes and cyclobutanes are now well-established in synthetic chemistry. Nevertheless, the potential of aminocyclopropanes and cyclobutanes, an important subcl ...

Royal Society of Chemistry2014

Diester-Substituted Aminocyclopropanes: Synthesis and Use in [3+2]-Annulation Reactions

Jérôme Waser, Florian Patrick Marie Daniel De la Barre De Nanteuil, Eloísa Sofía Serrano Robledo

In this Letter, we describe the synthesis of new donor-acceptor substituted cyclopropanes bearing various imido groups and their use in [3+2]-annulation reactions. A sequence of palladium-catalyzed vinylation and rhodium-catalyzed cyclopropanation gave acc ...

Georg Thieme Verlag2014

Diaminophosphine Oxide Ligand Enabled Asymmetric Nickel-Catalyzed Hydrocarbamoylations of Alkenes

Nicolai Cramer, Pavel Alexandrovich Donets

Chiral trivalent phosphorus species are the dominant class of ligands and the key controlling element in asymmetric homogeneous transition-metal catalysis. Here, novel chiral diaminophosphine oxide ligands are described. The arising catalyst system with ni ...

Amer Chemical Soc2013

Catalytic Formal Homo-Nazarov Reaction and Other Cyclizations of Cyclopropanes : from Methodology to Total Synthesis

Filippo De Simone

The increasing progress in medicinal chemistry and chemical biology requires more versatile synthetic strategies for the generation of libraries of active compounds and theirs analogues. A wide range of biologically active natural and synthetic compounds c ...

EPFL2012

Near-UV to red-emitting charged bis-cyclometallated iridium(III) complexes for light-emitting electrochemical cells

Michael Graetzel, Mohammad Khaja Nazeeruddin, Rosario Scopelliti, Davide Di Censo

Herein we report a series of charged iridium complexes emitting from near-UV to red using carbene-based (NC)-C-boolean AND: ancillary ligands. Synthesis, photophysical and electrochemical properties of this series are described in detail together with X-ra ...

Royal Society of Chemistry2012

Sequential ATRA-Reductive Cyclopropanation Reactions with a Ruthenium Catalyst in the Presence of Manganese

Kay Severin, Charlotte Buron

Atom-transfer radical addition (ATRA) reactions of ethyl trichloroacetate, dichloromalononitrile, or diethyl 2,2-dichloromalonate with olefins followed by dechlorination have provided functionalized cyclopropanes in one step. The RuIII complex [Cp*RuCl2(PP ...

Wiley-Blackwell2011

Cyclopropanes and Hypervalent Iodine Reagents: High Energy Compounds for Applications in Synthesis and Catalysis

Jérôme Waser, Stefano Nicolai, Jonathan Brand, Filippo De Simone, Davinia Fernández González

One of the major challenges faced by organic chemistry is the efficient synthesis of increasingly complex molecules. Since October 2007, the Laboratory of Catalysis and Organic Synthesis (LCSO) at EPFL has been working on the development of catalytic react ...

2011

Cyclization and Cycloaddition Reactions of Cyclopropyl Carbonyls and Imines

Jérôme Waser, Filippo De Simone

Activated cyclopropanes, such as vinyl and carbonyl cyclopropanes, are useful building blocks in organic chemistry due to their exceptional reactivity. This review focuses on the use of cyclopropyl carbonyls and imines in cyclization and cycloaddition reac ...

Georg Thieme Verlag2009

Cyclization of Cyclopropyl Carbonyls and the Homo-Nazarov Reaction

Jérôme Waser, Filippo De Simone

Ring strain confers to the cyclopropane ring an exceptional reactivity. Nevertheless, activation of the cyclopropane ring is usually needed to allow ring-opening reactions under mild conditions. The introduction of one or several carbonyl functionalities o ...

2009