Sonogashira versus Stephens-Castro Mediated Synthesis of o-Phenylethynylbenzoic Acids, Convenient Precursors of 3-Phenylisocoumarins

The 12th International Electronic Conference on Synthetic Organic Chemistry session General Organic SynthesisWe describe herein two synthetic approaches to 3-phenyl-5-nitro-isocoumarines, both based on a nitro-facilitated cyclization of o-phenylethynylbenzoic acids obtained by Sonogashira or Stephens-Castro mediated coupling of o-yodobenzoic acids and phenylacetilene