Chiral [2.2.2] dienes as ligands for Rh(I) in conjugate additions of boronic acids to a wide range of acceptors

reaction: see text] We document a series of investigations that led to new substituted 2.2.2]-diene ligands which display high selectivity in Rh(I)-catalyzed conjugate addition reactions to substrates not previously examined with diene ligands. Moreover, we disclose an unexpected, interesting effect that results from the introduction of a third C=C onto the ligand scaffold (cf. 1).