Université de Fribourg

Stereospecific hydrogenolysis of benzylic alcohols over Pd/C

Harvey, Freya M. ; Bochet, Christian G.

In: The Journal of Organic Chemistry, 2020, vol. 85, no. 11, p. 7611–7619

Hydrogenolysis of tertiary benzylic alcohols on palladium on carbon (Pd/C) generally proceeds with inversion of configuration. However, little is known about the hydrogenolysis mechanism of primary and secondary benzylic alcohols. Literature precedents suggest that these substrates may interact differently with the catalyst. To study the mechanism, we synthesized a pair of deuterated...

Université de Fribourg

Wavelength-Selective caged surfaces: how many functional levels are possible?

Miguel, Vernica San ; Bochet, Christian G. ; Campo, Arnzazu del

In: Journal of the American Chemical Society, 2011, vol. 133, no. 14, p. 5380–5388

The possibility of wavelength-selective cleavage of seven photolabile caging groups from different families has been studied. Amine-, thiol-, and carboxylic-terminated organosilanes were caged with o-nitrobenzyl (NVOC, NPPOC), benzoin (BNZ), (coumarin-4-yl)methyl (DEACM), 7-nitroindoline (DNI, BNI), and p-hydroxyphenacyl (pHP) derivatives. Caged surfaces modified with the different chromophores...

Université de Fribourg

Hard work and light experience: early steps in photochemistry

Bochet, Christian G.

In: Chimia, 2009, vol. 63, no. 12, p. 872-873

The author describes his early steps as an independent researcher at the University of Geneva. His interest in synthetic organic photochemistry came from his past non-experience at the Universities of Geneva and Stanford, where he worked mainly on natural product synthesis and transition-metal catalysis.

Université de Fribourg

Photoinduced acyl transfer

Débieux, Jean-Luc ; Bochet, Christian G.

In: Journal of Physical Organic Chemistry, 2010, p. -

The acylation reaction occupies a central role in biochemistry and organic synthesis. On the one hand, it is by this very reaction that amino acids successively assemble to form peptides and proteins, and on the other hand it is a major synthetic method encompassing esterification, amidation, Friedel-Crafts reaction and many other processes routinely used both at the laboratory and the industrial...

Université de Fribourg

Preparation of photoactivable amino acid derivatives

Débieux, Jean-Luc ; Bochet, Christian G.

In: Journal of Organic Chemistry, 2009, vol. 74, no. 12, p. 4519–4524

A range of N-protected-α-amino acyl-5,7-dinitroindolines 3a−z were prepared in good yields from commercially available N-protected-α-amino acids 1a−z by a two-step sequence of acylation and intramolecular amide N-arylation. Subsequent photochemical acylation of the N-protected-α-amino acyl-5,7-dinitroindolines 3e,g,r afforded the corresponding N-protected-α-amino acid amides 22e,g,r...

Université de Fribourg

Monitoring sterol uptake, acetylation, and export in yeast

Choudhary, Vineet ; Schneiter, Roger

In: Methods in Molecular Biology, 2009, vol. 580, p. 221-232

Sterols are essential lipid components of eukaryotic membranes. They are synthesized in the endoplasmatic reticulum (ER) from where they are efficiently transported to the plasma membrane, which harbors ~90% of the free sterol pool of the cell. The molecular mechanisms that govern this lipid transport, however, are not well characterized and are challenging to analyze. Saccharomyces cerevisiae...

Université de Fribourg

A dramatic difference between the electron-driven dissociation of alcohols and ethers and its relation to Rydberg states

Ibănescu, Bogdan C. ; Allan, Michael

In: Physical Chemistry Chemical Physics, 2008, vol. 10, p. 5232 - 5237

A difference was observed in the reactivity of alcohols and ethers toward free electrons. Whereas the lowest core-excited state of the negative ion—a ²(n,3s²) Feshbach resonance—of the alcohols readily dissociates by losing a hydrogen atom, ethers show no observable signal from this resonance. This difference in reactivity has a parallel in the anomalous shapes and energies of the...