Diastereoselective formation of indanes from arylboronate esters catalyzed by rhodium(I) in aqueous media.

ABSTRACT

[reaction see text] Arylboronate esters bearing a pendant Michael-acceptor alkene can add to norbornene and cyclize to give indane systems in yields ranging from 62% to 95% with high diastereomeric excess (>201). The reaction is performed in an organic/aqueous emulsion and catalyzed using [Rh(COD)Cl]2 with t-Bu-amphos chloride, a sterically bulky, electron-rich, water-soluble phosphine ligand.