Synthesis and use of a phosphoramidite ligand for the copper-catalyzed enantioselective allylic substitution. Tandem allylic substitution/ring-closing metathesis

A new one-pot method of reductive amination is used to prepare a chiral C2 symmetrical amine. This amine is used for the synthesis of a new chiral phosphoramidite ligand. The new ligand is, in turn, used to illustrate the enantioselective copper-catalyzed allylic substitution with Grignard reagents. When a remote double bond is located on the Grignard reagent, the newly formed alkene undergoes an in situ ruthenium-catalyzed ring-closing metathesis to afford the cyclized product in 77% yield and 94% ee.