Chiral binaphthyl ligands with buttressing substituents

Four macrocyclic and one non-cyclic chiral diphosphine ligand containing a 2,2'-substituted 1,1'-binaphthyl unit were synthesized in 6 steps from (R)- 2,2'-dimethoxy-1,1'-binaphthyl in overall yields of 8-51%. Their asymmetric induction in allylic alkylation reactions was investigated showing enantio selectivities up to 98%.