Synthesis of allenynes via Pd-catalyzed coupling of 1,4-diyn-3-yl carbonates with boronic acids

Abstract

Conjugated allenynes widely exist in natural products and are commonly employed in the development of functional materials. However, synthetic methods are very limited. In this contribution, a palladium-catalyzed cross-coupling reaction of 1,4-diyn-3-yl carbonates with a series of commercially available boronic acids using S-phos or Gorlos-phos as the ligand has been developed. Diversely substituted allenynes incorporating synthetically useful functional groups are obtained in good yields under this set of mild conditions. Gram-scale reactions and synthetic transformations have been conducted to show their potential utility.