Scheme 5. Mono- and Bidentate Coordination Equilibrium upon Reaction of (R)-1 with Organozinc Reagents.

(a) Depiction of the possible mono- and bidentate coordination species upon reaction of stable isomers of 1 with ZnR₂. (b) Only the isomers with a syn conformation (torsion angle = 0° to ±90°) were expected to efficiently bind a metal center and successfully transfer the chirality within a catalytically active complex. (c) Light-assisted dual stereocontrol could be achieved in a catalyzed organometallic reaction upon photoisomerization of (R)-1 and internal transfer of chirality to the coordinated metal site.