for the following products
(+)-1,4-bis-(Diphenylphosphino)-2,3-dihydroxy-2,3-o-isopropylidenebutane | (+)-DIOP | (4S,5S)-(+)-4,5-bis-(Diphenylphosphinomethyl)-2,2-dimethyl-1,3-dioxolane and (4R,5R)-(-)-O-isopropylidene-2,3-dihydroxy-1,4-bis-(diphenylphosphino)butane
