Solvent-free hydroboration of alkynes catalyzed by an NHC-cobalt complex
Małgorzata Bołt1, Patrycja Żak1
1Department of Organometallic Chemistry, Faculty of Chemistry, Adam Mickiewicz University in Poznan Uniwersytetu Poznańskiego 8 61-614 Poznan Poland pkw@amu.edu.pl.
Abstract:
A new cobalt complex bearing a bulky N-heterocyclic carbene (NHC) ligand is described as a pre-catalyst for alkyne hydroboration. The proposed catalytic system, synthesized using easily accessible reagents, allowed obtaining a series of mono- and dialkenylboranes in solvent-free conditions with excellent efficiency and selectivity. The results have been compared to those obtained in the presence of the same cobalt complex containing smaller NHC ligands and those achieved for the catalytic system based on a CoCl2 - NHC precursor.
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