Synthesis of B-protected beta-styrylboronic acids via iridium-catalyzed hydroboration of alkynes with 1,8-naphthalenediaminatoborane leading to iterative synthesis of oligo(phenylenevinylene)s.

Hydroboration of aromatic and aliphatic alkynes with 1,8-naphthalenediaminatoborane ((dan)BH) proceeded in the presence of [IrCl(cod)](2) complex with a DPPM or DPEphos ligand, affording alkenylboronic acids whose boronyl groups are masked by the diaminonaphthalene group. The masked alkenylboronic acids thus obtained from alkynes bearing halo-substituted aryl groups served as new coupling modules in an iterative Suzuki-Miyaura cross-coupling reaction for the synthesis of oligo(phenylenevinylene)s.