Enantioselective Synthesis of Planar-Chiral 1,n-Dioxa[n]paracyclophanes via Catalytic Asymmetric ortho-Lithiation
摘要:
Highly enantioselective ortho-lithiation and dilithiation of 1,n-dioxa[n]paracyclophanes were realized with the use of see-butyllithium and a catalytic or stoichiometric amount of sparteine. Quenching with various electrophiles, such as iodine, iodomethane, and chlorodiphenylphosphine, afforded chiral mono- and disubstituted paracyclophanes with good to excellent ee.
Enantioselective Synthesis of Planar-Chiral 1,n-Dioxa[n]paracyclophanes via Catalytic Asymmetric ortho-Lithiation
摘要:
Highly enantioselective ortho-lithiation and dilithiation of 1,n-dioxa[n]paracyclophanes were realized with the use of see-butyllithium and a catalytic or stoichiometric amount of sparteine. Quenching with various electrophiles, such as iodine, iodomethane, and chlorodiphenylphosphine, afforded chiral mono- and disubstituted paracyclophanes with good to excellent ee.