“…However, increasing the phosphine-to-rhodium ratio from 1 : 1 to 2 : 1 for the same ligand caused a complete reversal of the regioselectivity to 8 : 1 in favour of the Markovnikov product 46, entry 6, approaching the near complete regioselectivities previously observed by Hayashi in the rhodium-catalysed hydroboration of vinylarenes. [11,87] "Asymmetric amplification" experiments provided no evidence to suggest there was more than one phosphine ligand per catalyst molecule but did not conclusively rule out that possibility either. [94] Subsequently, Burgess [95] prepared a series of hybrid ligands 51 -53, Figure 5, which were chiral not only in the carbon backbone like (R,R)-DIOP (24), but also at phosphorus, like DIPAMP (50).…”