Publications de Stephanie Grace Elizabeth Amos

Exploring Photoredox-Catalyzed (Re)functionalizations with Core-Modified Benziodoxolones

Jérôme Waser, Franck Le Vaillant, Stephanie Grace Elizabeth Amos

Alkynes and nitriles are valuable building blocks in organic synthesis and also have multiple applications in chemical biology and materials science. Due to the high availability of tertiary alcohols, developing methods for their conversion into alkynes an ...

2022

Radical Alkynylations with EthynylBenziodoXolones: From Photocatalysis to Direct Excitation

Jérôme Waser, Stephanie Grace Elizabeth Amos

Ethynylbenziodoxolones (EBXs) have recently emerged as potent reagents for the alkynylation of radicals. Their combination with photocatalysis allows the synthesis of valuable alkynes at room temperature. Herein, we discuss two photomediated strategies for ...

2022

Photochemical Alkynylations with Hypervalent Iodine Reagents

Stephanie Grace Elizabeth Amos

Over the past twenty years, photochemical transformations have gained in importance in organic chemistry. Indeed, the development of photocatalysts has allowed the use of visible light as an energy source for chemical transformations. More specifically, ph ...

EPFL2022

Direct Photoexcitation of Ethynylbenziodoxolones: An Alternative to Photocatalysis for Alkynylation Reactions**

Jérôme Waser, Franck Le Vaillant, Stephanie Grace Elizabeth Amos, Diana Cavalli

Ethynylbenziodoxolones (EBXs) are commonly used as radical traps in photocatalytic alkynylations. Herein, we report that aryl-substituted EBX reagents can be directly activated by visible light irradiation. They act as both oxidants and radical traps, alle ...

Wiley-VCH Verlag GmbH2021

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

Photocatalytic Umpolung of N- and O-substituted alkenes for the synthesis of 1,2-amino alcohols and diols

Jérôme Waser, Stefano Nicolai, Stephanie Grace Elizabeth Amos

We report an organophotocatalytic 1,2-oxyalkynylation of ene-carbamates and enol ethers using Ethynyl BenziodoXolones (EBXs). 1-Alkynyl-1,2-amino alcohols and diols were obtained in up to 89% yield. Photocatalytic formation of radical cations led to Umpolu ...

2020

Metal-Free Electrophilic Alkynylation of Sulfenate Anions with Ethynylbenziodoxolone Reagents

Jérôme Waser, Stefano Nicolai, Franck Le Vaillant, Alec Gagnebin, Stephanie Grace Elizabeth Amos

Alkynyl sulfoxides are important building blocks with a unique reactivity in organic chemistry, but only a few reliable methods have been reported to synthesize them. A novel route to access alkynyl sulfoxides is reported herein by using ethynyl benziodoxo ...

2019