Publications related to Curtius rearrangement

Sustainable, recyclable and biodegradable castor oil-derived elastomers enabled by dynamic acetoacetyl formed amides

Developing sustainable, recyclable, and biodegradable elastomers with the mechanical properties comparable to commercial polymers presents a formidable challenge. To this end, we synthesize a kind of mechanically robust elastomers cross -linked by acetoace ...

Elsevier Science Sa2024

Enantioselective Total Synthesis of (+)-Stephadiamine

Qian Wang, Jieping Zhu, Baochao Yang, Guang Li

An asymmetric synthesis of (+)-stephadiamine has been accomplished featuring (a) an enantioselective dearomatizative Michael addition to generate a quaternary stereocenter; (b) a domino sequence involving reductive generation of nitrone from γ-nitro ketone ...

2023

Divergent Asymmetric Total Synthesis of (−)‐Voacafricines A and B

Qian Wang, Jieping Zhu, Rémi Julien Sylvain Andres

A divergent asymmetric total synthesis of voacafricines A and B, hexacyclic monoterpene indole alkaloids, has been accomplished featuring the following key steps: a)a catalyst-controlled asymmetric Pictet– Spengler reaction of 6-methoxytryptamine with a ch ...

Wiley-VCH Verlag GmbH2023

Diamine Synthesis via the Nitrogen-Directed Azidation of sigma- and pi-C-C Bonds

Jérôme Waser, Mingming Wang

Diamines are essential building blocks for the synthesis of agrochemicals, drugs, and organic materials, yet their synthesis remains challenging, as both nitrogens need to be differentiated and diverse substitution patterns (1,2, 1,3, or 1,4) are required. ...

2021

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

Insertion of germanium atoms in high- nuclearity rhodium carbonyl compounds: synthesis, characterization and preliminary biological activity of the heterometallic [ Rh13Ge( CO) 25] 3-, [ Rh14Ge2( CO) 30] 2-and [ Rh12Ge( CO) 27] 4-clusters+

Paul Joseph Dyson, Silvia Ruggieri

The reaction of the Rh-7(CO)(16) cluster anion with Ge2+ salts, in different stoichiometric ratios and under different atmospheres, leads to the formation of new heterometallic Rh-Ge clusters, representing the first known examples of Rh carbonyl comp ...

ROYAL SOC CHEMISTRY2018

Organocatalytic Enantioselective Acyloin Rearrangement of α-Hydroxy Acetals to α-Alkoxy Ketones

Qian Wang, Jieping Zhu, Hua Wu

We report an unprecedented organocatalytic enantioselective acyloin rearrangement of alpha,alpha-disubstituted alpha-hydroxy acetals. In the presence of a catalytic amount of chiral binol-derived N-triflyl phosphoramide, alpha-hydroxy acetals rearranged to ...

Wiley-Blackwell2017

Morphology stabilization strategies for small-molecule bulk heterojunction photovoltaics

Kevin Sivula, Liang Yao, Xavier Adrian Jeanbourquin, Simon Hänni, Arvindh Sekar, Emilie Aude Marie Ripaud, Muhammad Aiman Bin Rahmanudin Hamdan

The greater crystallinity of solution-processed small-molecule organic semiconductors, compared to their polymer counterparts, renders the bulk heterojunction (BHJ) more susceptible to phase separation under thermal stress, decreasing device performance. H ...

Royal Society of Chemistry2017

Zinc Bromide Promoted Coupling of Isonitriles with Carboxylic Acids To Form 2,4,5-Trisubstituted Oxazoles

Qian Wang, Jieping Zhu, Shuo Tong

Deviant behavior: In a deviation from “normal” reactivity, isocyanides underwent co-trimerization with carboxylic acids in the presence of ZnBr2 to smoothly provide oxazoles (see scheme). The reaction is thought to occur by initial nucleophilic addition of ...

Wiley-Blackwell2013

Amide Formation in One Pot from Carboxylic Acids and Amines via Carboxyl and Sulfinyl Mixed Anhydrides

Pierre Vogel, Dean Markovic

An efficient method has been developed for the preparation of yet unknown acyclic mixed anhydrides of carboxylic and sulfinic acids. Sterically hindered 2-methylbut-3-ene-2-sulfinyl carboxylates add primary and secondary amines preferentially onto the carb ...

Amer Chemical Soc2013

Conformation-Specific Spectroscopy of Peptide Fragment Ions in a low-Temperature Ion Trap

Thomas Rizzo, Oleg Boyarkine

We have applied conformer-selective IR-UV double-resonance photofragment spectroscopy at low temperatures in an ion trap mass spectrometer for the spectroscopic characterization of peptide fragment ions. We investigate b- and a-type ions formed by collisio ...

Springer-Verlag2012

Functional, Hyperbranched Polyesters Via Baylis-Hillman Polymerization

Harm-Anton Klok, Sanhao Ji, Frederik Roman Wurm

Hyperbranched polyesters are among the most common hyperbranched polymers. One of the interesting features of hyperbranched polyesters is that they contain unreacted hydroxyl and carboxylic acid groups at the linear and terminal structural units, which can ...

2012

Synthesis of Side-Chain Functional Polyesters via Baylis-Hillman Polymerization

Harm-Anton Klok, Sanhao Ji

Strategies that allow access to side-chain functional polyesters are valuable as they would enable to engineer the properties of these hydrolytically degradable materials. This contribution explores the feasibility of a novel approach toward side-chain fun ...

American Chemical Society2011

Nouvelles approches synthétiques de prodrogues de cyclosporine A et d'analogues antiviraux

Jérémy Bérard

The cyclosporins comprise a family of cyclic 11-peptides containing seven N-methylated, hydrophobic amino acids. Cyclosporine A (CsA) representing the major member of this family is widely used as immunosuppressive agent in organ transplantations. The biol ...

EPFL2008

Switch-peptides as folding precursors in self-assembling peptides and amyloid fibrillogenesis

Hilal Lashuel, Adrian Schmid, Karine Murat, Richard Alan Mimna, Marie-Stéphanie Camus, Jérémy Bérard

The study of conformational transitions of peptides has obtained considerable attention recently because of their importance as a mol. key event in a variety of degenerative diseases. However, the study of peptide self-assembly into beta-sheets and amyloid ...

2007

Switch-peptides as folding precursors in amyloid fibrillogenesis

Sonia Dos Santos, Richard Alan Mimna, Karine Murat, Lydiane Jeanine Saucède, Marie-Stéphanie Camus, Jérémy Bérard

Intramol. O,N-acyl migration reactions were used as structural switch (S-elements) from a depsipeptide bond contg., unfolded state (Soff) to an all-amide, native states (Son). Chem. or enzymically triggered acyl migrations allowed for the controlled induct ...

2006

Le réarrangement [1,2] de Wittig : contribution à l'étude de son mécanisme et de ses applications

Frédéric Bailly

The importance of catalysis in chemistry has not to be proved anymore. Be it homogeneous or heterogeneous catalysis, the constant progresses observed in that field proves its obvious interest. The asymmetric homogeneous catalysis is a method of choice to s ...

EPFL2005

Switch-peptides: controlling biological function and self-assembly of amyloid ß-derived peptides using enzyme-triggered acyl migrations

Sonia Dos Santos

Conformational transitions of peptides and proteins have recently moved to the center of interest in various domains of research at the interface of chemistry, biology, and medicine due to their implication in an increasing number of diseases in which the ...

EPFL2005