Noyori and his co-workers developed a chiral diphosphine ligand

Phosphine can complex to transition metals through the lone pair of electrons on the phosphorus atom. Replacing the hydrogen atoms with other groups can give chiral ligands, and so chiral catalysts.

Noyori's diphosphine ligand, called BINAP

It is chiral because the fused ring systems have to twist as you can see in the 3-D image