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Chiral C2-symmetric bis (oxazoline) s have been successfully employed as ligands with various metals in numerous catalytic asymmetric processes. These include cyclopropanation, 2 aziridination, 3 allylic substitution, 4 hydrosilylation, 5 imine additions, 6 Diels-Alder, 7 aldol, 8 and Wacker-type cyclization9 reactions. In addition we and Pfaltz have recently used bis (oxazoline) copper complexes as catalysts for the asymmetric allylic oxidation of simple olefins using tert-butyl perbenzoate. 10 While the linker between the oxazolines in the past have consisted of a methylene unit, derived from a malonyl precursor, or a pyridyl unit, recently Corey reported the synthesis of a unique biaryl-linked ligand, 1, 1′-bis-o-tolyl-2, 2′-bis (oxazoline), for use in a highly selective intramolecular copper-catalyzed cyclopropanation reaction leading to (-)-sirenin. 11 This new catalyst was shown to superior to a variety of known metal …