Rhodium- and ruthenium-catalyzed dehydrogenative borylation of vinylarenes with pinacolborane: Stereoselective synthesis of vinylboronates

Article abstract of DOI:10.1246/bcsj.75.825

The treatment of pinacolborane (4,4,5,5-tetramethyl-1,3,2- dioxaborolane) with vinylarenes in the presence of a catalytic amount of phosphine-free di-μ-chlorobis(1,5- cyclooctadiene)dirhodium(I) [RhCl(cod)]₂, through dehydrogenative borylation, provides the corresponding regio- and stereodefined (E)-2-arylethenylboronates in high yields. Also, a ruthenium complex prepared in situ from (1,5-cyclooctadiene)(1,3,5-cyclooctatriene)ruthenium(O) [Ru(cod)(cot)] and P(4CF₃C₆H₄)₃ showed considerable catalytic activity for dehydrogenative borylation.