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Publications associées (30)

Novel Alkynylation Methods through the Combination of Hypervalent Iodine Reagents and Alkynyl-trifluoroborate Salts

The alkyne motif is a versatile functional group often encountered in organic chemistry. It can be involved in various transformations such as the alkyne-azide cycloaddition and has found widespread application in medicinal chemistry, chemical biology and ...

EPFL2024

Origin of metallic-like behavior in disordered carbon nano-onions

Oleg Yazyev, Kristians Cernevics

Carbon nano-onions are a class of nanomaterials that can exhibit long electron spin relaxation times at room temperature and thus hold promise as potential building blocks for spintronics and quantum information processing devices. Despite first being synt ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Synthesis of Four-Membered BN3 Heterocycles by the Borylation of Triazenes

Rosario Scopelliti, Kay Severin, Abdusalom Suleymanov

Borylated triazenes were synthesized by the dehydrocoupling of triazenes with 9-borabicyclo(3.3.1)nonane, by the condensation of triazenes with BEt3, or by the reaction of sodium triazenides with dialkyl- or diarylboron halides. The structures of the produ ...

2022

New Vinylation and Alkynylation Strategies with Hypervalent Iodine Reagents and Diazo Compounds

Guillaume Dominique Pisella

The development of a sequential copper-catalyzed oxy-alkynylation/intramolecular [4+2] cycloaddition of allenes and arenes was investigated at first. This one-pot protocol allowed the construction of complex polycylic architectures with high efficiency fro ...

EPFL2021

New Strategies for the Functionalization of Alkenes Exploiting Tethering Chemistry and Ring Strain

Bastian Antoine Rodolphe Claude Muriel

Amino alcohols, cyclopropanes and nitriles are privileged structural motifs found in the scaffold of natural products and bioactive compounds. In addition, they are versatile building blocks in organic chemistry. The development of new and increasingly eff ...

EPFL2021

Ligand Effects in Low-Valent Co(I) Clathrochelate Complexes

Rosario Scopelliti, Kay Severin, Farzaneh Fadaei Tirani, Ophélie Marie Planes

Clathrochelate complexes of cobalt are known in the oxidation states I, II, and III. Low-valent Co(I) complexes are highly reactive compounds, and there is only limited knowledge about their structures in the solid state. Herein, we describe the crystallog ...

2021

Combining cryognic ion spectroscopy with ion mobility for the study of glycan fragmentation

Robert Paul Pellegrinelli

The importance of glycans in biological processes are matched by their structural complexity. Coating the surface of most living cells, glycans play key roles in many biological processes, and the role they play is closely related to their structures. Stru ...

EPFL2021

Investigating Tetrel-Based Neutral Frustrated Lewis Pairs for Hydrogen Activation

Shubhajit Das

Tetrel Lewis acids are a prospective alternative to commonly employed neutral boranes in frustrated Lewis pair (FLP) chemistry. While cationic tetrylium Lewis acids, being isolobal and iso(valence)electronic, are a natural replacement to boranes, neutral t ...

AMER CHEMICAL SOC2021

Probing Substrate Scope with Molecular Volcanoes

Matthew Wodrich, Anne-Clémence Corminboeuf, Boodsarin Sawatlon

Molecular volcano plots, a tool generally used to identify ideal catalysts for a given chemical transformation, are employed in an alternative fashion to examine the substrate scope by revealing the range of substrates that can be accommodated by a single ...

AMER CHEMICAL SOC2020

Synthetic Studies toward Amanita Phalloides Toxins

Philipp Georg Werner Seeberger

Amatoxins are ribosomally synthesized and post-translationally modified bicyclic octapeptides biosynthesized by the deadly basidiomycete fungus Amanita phalloides. Amongst this group, alpha-amanitin is the most widely known toxin and is currently under inv ...

EPFL2020

Bi-stable spin-crossover in charge-neutral [Fe(R-ptp)(2)] (ptp=2-(1H-pyrazol-1-yl)-6-(1H-tetrazol-5-yl)pyridine) complexes

Sergio Vela Llausi

Bi-stable charge-neutral iron(II) spin-crossover (SCO) complexes are a class of switchable molecular materials proposed for molecule-based switching and memory applications. In this study, we report on the SCO behavior of a series of iron(II) complexes com ...

2020

Chlorination of Phenols Revisited: Unexpected Formation of α,β-Unsaturated C4-Dicarbonyl Ring Cleavage Products

Urs von Gunten

Despite decades of research on the fate of phenolic compounds when water is disinfected with hypochlorous acid (HOCl), there is still considerable uncertainty regarding the formation mechanisms and identity of ring cleavage products, especially at higher c ...

2020

Trisubstituted geminal diazaalkene derived transient 1,2-carbodications

Shubhajit Das

The coulombic repulsion between two adjacent cation centres of 1,2-carbodications is known to decrease with pi- and/or n-donor substituents by a positive charge delocalization. Here we report the delocalization of the positive charge of transient 1,2-carbo ...

Royal Society of Chemistry2020

Fused N‐Heterocycles with Contiguous Stereogenic Centers Accessed by an Asymmetric Catalytic Cascade Reaction of Tertiary Enamides

Jieping Zhu, Shuo Tong

We report in this article a cascade reaction strategy for the synthesis of complex N-heterocyclic compounds with contiguous and tetrasubstituted stereogenic carbons. Under the sequential catalysis of a chiral binol–Ti complex and BF3, cyclopentanone-derive ...

2020

Antiproliferative Activities of Diimine-Based Mixed Ligand Copper(II) Complexes

Rosario Scopelliti

A series of Cu(diimine)(X-sal)(NO3) complexes, where the diimine is either 2,2'-bipyridine (bpy) or 1,10-phenanthroline (phen) and X-sal is a monoanionic halogenated salicylaldehyde (X = Cl, Br, I, or H), have been synthesized and characterized by elementa ...

AMER CHEMICAL SOC2020

Interfacial and bulk properties of hole transporting materials in perovskite solar cells: spiro-MeTAD versus spiro-OMeTAD

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Elham Halvani Anaraki, Mona Shasti

Two spiro-MeTAD compounds (1 and 2) were synthesized, characterized by experimental and quantum mechanical methods, and used as hole transporting materials (HTMs) in perovskite solar cells (PSCs). The new compounds differ from spiro-OMeTAD only by the pres ...

Royal Society of Chemistry2020

Divergent Synthesis of Densely Substituted Arenes and Pyridines via Cyclotrimerization Reactions of Alkynyl Triazenes

Kay Severin, Nicolai Cramer, Carl Thomas Bormann, Florian Gérald Abela, Jin Fay Tan, Frederick Mark Chadwick

Densely substituted fused aromatic triazenes can be prepared by [2 + 2 + 2] cyclotrimerization reactions of 1-alkynyl triazenes. The Cp*Ru-catalyzed cyclization proceeds well with both simple alkynyl triazenes and tethered 1-diynyl triazenes. Attractively, ...

2019

Hydrothermally Stable Sulfonated Carbons as Solid Acid Catalysts for the Hydrolysis of Lignocellulose

David Ferdinand Scholz

The recycling of homogeneous acids imposes great challenges to the feasibility of lignocellulose hydrolysis processes. Although heterogeneous catalysts would offer a perspective to circumvent these challenges, conventional solid acids are instable under th ...

EPFL2019

Perovskite Solar Cells: 18% Efficiency Using Zn(II) and Cu(II) Octakis(diarylamine)phthalocyanines as Hole-Transporting Materials

Mohammad Khaja Nazeeruddin, Sanghyun Paek, Kyung Taek Cho, Kasparas Rakstys, Hiroyuki Kanda, Valentin Ianis Emmanuel Queloz, Marius Franckevicius

Metallophthalocyanines (MPcs) are currently emerging as alternative hole-transporting materials (HTMs) in perovskite solar cells (PSCs). However, the lack of systematic structure/photovoltaic properties investigations still hampers the rational design of M ...

2019

Multiarm and Substituent Effects on Charge Transport of Organic Hole Transport Materials

Mohammad Khaja Nazeeruddin, Kevin Sivula, Liang Yao, Antonio Prlj, Kun-Han Lin, Nikita Drigo, Han-Hee Cho

We explore several potential dopant-free triphenylamine-based hole transport materials for perovskite solar cells by combining two design strategies: (1) incorporation of multiple arms for mobility enhancement and (2) including Lewis bases that assist in d ...

2019