Publications associées à Carbocation

Investigations about the Chemistry of Tetraarylethene- and Iridium-Based Luminophores

The work described in this thesis focuses on two classes of luminophores: tetraarylethene-based polymers and Ir(III) complexes with orthometalated ligands. Tetraarylethene-based polymers show aggregation-induced emission (AIE) and they are of interest for ...

EPFL2024

New Applications of 1,3,2-Diazaphospholenes in Catalysis

Johannes Klett

The constant urge to construct new molecules in an economical and sustainable fashion led to the development of numerous metal-catalyzed transformations. Organocatalysts consisting of abundant and more sustainable elements offer an elegant solution to over ...

EPFL2024

Development of Hetero-Vinylbenziodoxolone Reagents for Applications in Synthetic Methodology and Biomolecule Functionalization

Nina Declas

Among the numerous existing chemical motifs, alkenes, alkynes, enol ethers and enamides, with an unsaturated carbon-carbon bond, are versatile functional groups that are found in many natural products and bioactive compounds. They are widely used as valuab ...

EPFL2023

Semipinacol Rearrangement of Cyclopropenylcarbinols for the Synthesis of Highly Substituted Cyclopropanes

Jérôme Waser, Vladyslav Smyrnov

An electrophile-induced semipinacol rearrangement of cyclopropenylcarbinols is reported. This transformation gives access to various polyfunctionalized cyclopropanes under mild metal-free conditions. The scope of the reaction includes iodine, sulfur and se ...

2023

(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

Tuning Napththalenediimide Cations for Incorporation into Ruddlesden–Popper-Type Hybrid Perovskites

Jacques-Edouard Moser, Kevin Sivula, Jun Ho Yum, Liang Yao, Etienne Christophe Socie, Simon Nussbaum

Layered hybrid organic−inorganic perovskite (LHOIP) materials constructed with low-band-gap chromophore-based organic spacer cations are anemerging class of materials that promise unique tunability of their optoelectronic properties. However, the large siz ...

2022

Catalytic Enantioselective Pictet–Spengler Reaction of α‐Ketoamides Catalyzed by a Single H‐Bond Donor Organocatalyst

Jieping Zhu, Qiang Wang, Rémi Julien Sylvain Andres

The asymmetric Pictet–Spengler reaction (PSR) with aldehydes is well known. However, PSR involving ketones as electrophilic partners is far-less developed. We report herein the first examples of catalytic enantioselective PSR of tryptamines with α-ketoamid ...

Wiley-VCH Verlag GmbH2022

Access to Vinyl Ethers and Ketones with Hypervalent Iodine Reagents as Oxy-Allyl Cation Synthetic Equivalents

Jérôme Waser, Nina Declas

We report an Umpolung strategy of enol ethers to generate oxy-allyl cation equivalents based on the use of hypervalent iodine reagents. Under mild basic conditions, the addition of nucleophiles to aryloxy-substituted vinylbenziodoxolone (VBX) reagents, eas ...

Wiley-VCH Verlag GmbH2020

Photocatalysis with organic dyes: facile access to reactive intermediates for synthesis

Jérôme Waser, Marion Marie-Agnès Garreau, Stephanie Grace Elizabeth Amos, Luca Buzzetti

Organic dyes have emerged as a reliable class of photoredox catalysts. Their great structural variety combined with the easy finetuning of their electronic properties has unlocked new possibilities for the generation of reactive intermediates. In this revi ...

2020

SET processes in Lewis acid–base reactions: the tritylation of N-heterocyclic carbenes

Rosario Scopelliti, Kay Severin, Farzaneh Fadaei Tirani, Andrzej Sienkiewicz, Cristian Pezzato, Zhaowen Dong

Reactions between N-heterocyclic carbenes (NHCs) and the trityl cation, [Ph3C]+, give covalent adducts of type [NHC–CPh3]+ and/or [NHC–C6H5–CPh2]+. EPR spectroscopy, UV-Vis analyses, and trapping experiments imply that adduct formation involves carbene rad ...

2020