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The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Ruthenium-Catalyzed Regioselective 1,4-Hydroboration of Pyridines
Akash Kaithal1, Basujit Chatterjee1, Chidambaram Gunanathan1
1School of Chemical Sciences, National Institute of Science Education and Research (NISER) , Bhubaneswar-752 050, India.
Abstract:
Simple ruthenium precursor [Ru(p-cymene)Cl2]2 1 catalyzed regioselective 1,4-dearomatization of pyridine derivatives using pinacolborane is reported. Two catalytic intermediates, [Ru(p-cymene)Cl2Py] 2 and [Ru(p-cymene)Cl2(P(Cy)3)] 3, involved in this process are identified, independently synthesized, characterized, and further used directly as effective catalysts; two more catalytic intermediates [Ru(p-cymene)Cl2(Py)(P(Cy)3)] 4 and [Ru(p-cymene)(H)Cl(Py)(P(Cy)3)] 5 are identified in solution. Complex 5 is the active catalytic intermediate. An intramolecular selective 1,5-hydride transfer in 5 leading to the regioselective 1,4-hydroboration of pyridine compounds is proposed.
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