Publications associées à Ring (chemistry)

Lewis acid catalyzed [4+2] annulation of bicyclobutanes with dienol ethers for the synthesis of bicyclo[4.1.1]octanes

Bicyclic carbocycles containing a high fraction of Csp3 have become highly attractive synthetic targets because of the multiple applications they have found in medicinal chemistry. The formal cycloaddition of bicyclobutanes (BCBs) with two- or three-atom p ...

Royal Soc Chemistry2024

Double-bond delocalization in non-alternant hydrocarbons induces inverted singlet-triplet gaps

Anne-Clémence Corminboeuf, Jacob Terence Blaskovits, Marc Hamilton Folkmann Garner

Molecules where the first excited singlet state is lower in energy than the first excited triplet state have the potential to revolutionize OLEDs. This inverted singlet-triplet gap violates Hund's rule and currently there are only a few molecules which are ...

ROYAL SOC CHEMISTRY2023

Double-bond delocalization in non-alternant hydrocarbons induces inverted singlet-triplet gaps

Anne-Clémence Corminboeuf, Jacob Terence Blaskovits, Marc Hamilton Folkmann Garner

Molecules where the first excited singlet state is lower in energy than the first excited triplet state have the potential to revolutionize OLEDs. This inverted singlet-triplet gap violates Hund's rule and currently there are only a few molecules which are ...

ROYAL SOC CHEMISTRY2023

Azide Radical Initiated Ring Opening of Cyclopropenes Leading to Alkenyl Nitriles and Polycyclic Aromatic Compounds

Jérôme Waser, Bastian Antoine Rodolphe Claude Muriel

We report herein a radical‐mediated amination of cyclopropenes. The transformation proceeds through a cleavage of the three‐membered ring after the addition of an azide radical on the strained double bond and leads to tetrasubstituted alkenyl nitrile deriv ...

Wiley-VCH Verlag GmbH2020

Developing Reactions of Strained Rings : Enantioselective Desymmetrization of meso-Diaminocyclopropanes and Annulation of Donor-Acceptor Aminocyclobutanes

Daniele Perrotta

Carbo- and heterocyclic structures containing nitrogen-substituted stereocenters are recurrent structural motifs in natural and bioactive compounds, therefore constituting a privileged class of synthetic targets. In this regard, substituted three- and four ...

EPFL2018

Indole- and Pyrrole-BX: Bench-Stable Hypervalent Iodine Reagents for Heterocycle Umpolung

Jérôme Waser, Stefano Nicolai, Paola Caramenti

The one-step synthesis of the bench-stable hypervalent iodine reagents IndoleBX and PyrroleBX using mild Lewis acid catalyzed conditions is reported. The new reagents are stable up to 150 degrees C and were applied in the C-H arylation of unactivated arene ...

2017

Charge transporting material for optoelectronic and/or photoelectrochemical devices

Michael Graetzel, Mohammad Khaja Nazeeruddin, Paul Gratia, Iwan Zimmermann, Inés Garcia Benito

The present invention relates to an optoelectronic and/or photoelectrochemical device comprising at least one organic-inorganic perovskite as sensitizer and at least one compound of formula (I) comprising one benzotrithiophene core Q, wherein each thiophen ...

2017

Divergent Asymmetric Synthesis of Polycyclic Compounds via Vinyl Triazenes

Rosario Scopelliti, Kay Severin, Nicolai Cramer, Gregor Kiefer, Abdusalom Suleymanov, Florian Gérald Abela, David Kossler

Vinyl triazenes were obtained by enantioselective [2+2] cycloaddition reactions of bicyclic alkenes with 1-alkynyl triazenes in the presence of a RuII catalyst with a chiral cyclopentadienyl ligand. These triazenes serve as unique vinyl cation surrogates. ...

Wiley-VCH Verlag GmbH2017

Phase transfer based chemical sensing

Francesco Stellacci, Stefan Guldin, Yang Ye

The present invention relates to a phase transfer based chemical sensing, specifically to a method for selective separation, detection and quantification of a polycyclic organic compound in a sample and a method for selective extraction of a polycyclic org ...

2016

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

Lewis acid Catalyzed Annulations of Donor-Acceptor Aminocyclopropanes and Aminocyclobutanes

Sophie Lucie Racine

Organic molecules are indispensable have greatly contributed to the confort of our modern life. Nevertheless, humanity is facing now new challenges such as environmental issues and emerging drug resistances. In order to solve these major concerns, chemists ...

EPFL2016

Synthesis of Alkynylated Heterocycles by Direct C-H Alkynylation or Domino Alkynylation Reactions

Yifan Li

Heterocycles are important compounds in organic chemistry. To introduce functional groups on heterocycles or synthesize functionalized heterocycles stays a hot topic of research. Among all the functional groups, alkynes attracted a lot of attention not onl ...

EPFL2016

Catalytic C-C Bond Activations via Oxidative Addition to Transition Metals

Nicolai Cramer, Laetitia Marie Mélanie Souillart

Selective cleavages of carbon-carbon bonds catalyzed by transition-metal complexes have been shown to be increasingly versatile tools for organic synthesis allowing for complementary synthetic strategies. Numerous examples of transition-metal catalyzed C-C ...

Amer Chemical Soc2015

Access to beta-Lactams by Enantioselective Palladium(0)-Catalyzed C(sp(3))-H Alkylation

Nicolai Cramer, Tanguy Jean Daniel Saget, Julia Pedroni, Michele Boghi

beta-Lactams are very important structural motifs because of their broad biological activities as well as their propensity to engage in ring-opening reactions. Transitionmetal- catalyzed C-H functionalizations have emerged as strategy enabling yet uncommon ...

Wiley-Blackwell2014

Enantioselective Synthesis of Polycyclic Carbocycles via an Alkynylation-Allylation-Cyclization Strategy

Jérôme Waser, Pascal Miéville, Maria Victoria Vita

A new general three-stage strategy to access polycyclic ring systems bearing all-carbon quaternary centers with high enantioselectivity is reported. The required starting materials were readily accessed in racemic form through the alpha-alkynylation of ket ...

American Chemical Society2014

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

Exploiting the Divergent Reactivity of Isocyanoacetates: One-Pot Three-Component Synthesis of Functionalized Angular Furoquinolines

Jieping Zhu

A one-pot, three-component synthesis of polysubstituted furo[2,3-c] quinoline 1 was developed based on the new reactivity profile of alpha-(4-nitrophenyl)-alpha-isocyanoacetates. Simply mixing aldehydes 2, ortho-alkynylanilines 3, and alpha-(4-nitrophenyl) ...

2012

Spirocyclization by Palladium-Catalyzed Domino Heck–Direct C–H Arylation Reactions: Synthesis of Spirodihydroquinolin-2-ones

Jieping Zhu

Treatment of a DMA solution of anilide 1 with a catalytic amount of palladium acetate (0.025 equiv) and XPhos (0.05 equiv) in the presence of potassium carbonate (2.0 equiv) at 100 C afforded dihydroquinolin-2-ones spiro-fused to dihydrofuranyl, indolinyl, ...

2012

Formal Homo-Nazarov and Other Cyclization Reactions of Activated Cyclopropanes

Jérôme Waser, Fides Benfatti, Filippo De Simone, Tanguy Jean Daniel Saget

The Nazarov cyclization of divinyl ketones gives access to cyclopentenones. Replacing one of the vinyl groups by a cyclopropane leads to a formal homo-Nazarov process for the synthesis of cyclohexenones. In contrast to the Nazarov reaction, the cyclization ...

2011

Catalytic Formal Homo-Nazarov Cyclization

Jérôme Waser, Julien Alexandre Andres, Filippo De Simone, Riccardo Torosantucci

The first catalytic method for the cyclization of vinyl-cyclopropyl ketones (formal homo-Nazarov reaction) is reported. Starting from activated cyclopropanes, heterocyclic and carbocyclic compounds were obtained under mild conditions using Brønsted acid ca ...

American Chemical Society2009