Facile and racemization-free conversion of chiral nitriles into pyridine derivatives

The results described herein demonstrate how the very mild reaction conditions of the Co(I)catalyzed photochemical [2 + 2 + 2] cyclocotrimerization are suited to prepare chiral compounds containing unsubstituted and polysubstituted 2-pyridyl moieties starting from chiral nitriles without any detectable loss of enantiomerical purity. This further increases the already very broad synthetic scope of this particular reaction.