Oxazoles, Negishi cross-coupling reactions

Elaborations of the oxazole scaffold included the first stepwise and mild functionalization performed through subsequent Mg or Zn metallation steps in positions 2, 4, and finally 5. The metallation allowed reactions with electrophiles, Negishi cross-couplings, Pd-catalyzed Negishi acylations, Sono-gashira couplings and, after transmetallation with Cu, allylations (130L6162). 

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