Organocobalt-catalysed synthesis pyridines

Bonnemann, H., Brijoux, W., Organocobalt-Catalysed Synthesis of Pyridines,... 

Bojarski, I. T., Mokrosz, I. L., Barton, H. J., Paluchowska, M. H., Recent Progress in Barbituric Acid Chemistry, 38, 229. Bonnemann, H., Brijoux, W., Organocobalt-Catalysed Synthesis of Pyridines,... 

The organocobalt catalysed synthesis of substituted pyridines from alk-l-enes and nitriles (Equation 22) has been extended further by the discovery that the leaction is catalysed by cobaltocene, Co(i7 -05145)2, a more easily obtained complex than earlier catalysts.Acetylene reacts with substituted nitriles to give 2-sub-stituted pyridines in up to 60% yield, whereas mono-substituted acetylenes react to give mixtures of 2,4,6- and 2,3,6-trisubstituted pyridines in moderate yield. 

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