Highly enantioselective catalytic synthesis of chiral pyridines
Ravindra P Jumde1, Francesco Lanza1, Tilde Pellegrini1
1Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
Abstract:
General methods to prepare chiral pyridine derivatives are greatly sought after due to their significance in medicinal chemistry. Here, we report highly enantioselective catalytic transformations of poorly reactive β-substituted alkenyl pyridines to access a wide range of alkylated chiral pyridines. The simple methodology involves reactivity enhancement via Lewis acid (LA) activation, the use of readily available and highly reactive Grignard reagents, and a copper-chiral diphosphine ligand catalyst. Apart from allowing the introduction of different linear, branched, cyclic, and functionalised alkyl chains at the β-position of alkenyl pyridines, the catalytic system also shows high functional group tolerance.
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