Publications de Jan Breitenfeld

Bimetallic Oxidative Addition in Nickel-Catalyzed Alkyl-Aryl Kumada Coupling Reactions

Matthew Wodrich, Xile Hu, Jan Breitenfeld

The mechanism of alkylaryl Kumada coupling catalyzed by the nickel pincer complex Nickamine was studied. Experiments using radical-probe substrates and DFT calculations established a bimetallic oxidative addition mechanism. Kinetic measurements showed that ...

American Chemical Society2014

Mechanistic Insights into Nickamine-catalyzed Alkyl-Alkyl Cross-coupling Reactions

Xile Hu, Jan Breitenfeld

Within the last decades the transition metal-catalyzed cross-coupling of non-activated alkyl halides has significantly progressed. Within the context of alkyl-alkyl cross-coupling, first row transition metals spanning from iron, over cobalt, nickel, to cop ...

Schweizerische Chemische Gesellschaft2014

Mechanistic Studies Related to Nickel-Catalyzed Alkyl-Alkyl Cross Coupling Reactions

Jan Breitenfeld

Cross-coupling reactions of non-activated alkyl halides are potentially useful chemical transformations. At the same time, however, they are challenging due to a series of unproductive side reactions. Recently, significant progress has been made to overcom ...

EPFL2013

Bimetallic Oxidative Addition Involving Radical Intermediates in Nickel-Catalyzed Alkyl-Alkyl Kumada Coupling Reactions

Jesus Ruiz, Matthew Wodrich, Xile Hu, Jan Breitenfeld

Many nickel-based catalysts have been reported for cross-coupling reactions of nonactivated alkyl halides. The mechanistic understanding of these reactions is still primitive. Here we report a mechanistic study of alkyl-alkyl Kumada coupling catalyzed by a ...

American Chemical Society2013

Synthesis, Reactivity, and Catalytic Application of a Nickel Pincer Hydride Complex

Rosario Scopelliti, Xile Hu, Jan Breitenfeld

The nickel(II) hydride complex [(MeN2N)Ni-H] (2) was synthesized by the reaction of [(MeN2N)Ni-OMe] (6) with Ph2SiH2 and was characterized by NMR and IR spectroscopy as well as X-ray crystallography. 2 was unstable in solution, and it decomposed via two re ...

American Chemical Society2012

Why are (NN2)Ni pincer complexes active for alkyl-alkyl coupling: ß-H elimination is kinetically accessible but thermodynamically uphill

Rosario Scopelliti, Anne-Clémence Corminboeuf, Oleg Vechorkin, Xile Hu, Jan Breitenfeld

Isomerization and olefin exchange experiments show that β-H elimination is kinetically viable but thermodynamically unfavorable in [(MeNN2)Ni-alkyl] complexes. The intermediacy of Ni-hydride species was corroborated by a trapping experiment. The alkyl comp ...

American Chemical Society2010