Enantioselective Pd(II)-catalyzed aerobic oxidative amidation of alkenes and insights into the role of electronic asymmetry in pyridine-oxazoline ligands.

ABSTRACT: Enantioselective intramolecular oxidative amidation of alkenes has been achieved using a (pyrox)Pd(II)(TFA)(2) catalyst (pyrox = pyridine-oxazoline, TFA = trifluoroacetate) and O(2) as the sole stoichiometric oxidant. The reactions proceed at room temperature in good-to-excellent yields (58-98%) and with high enantioselectivity (ee = 92-98%). Catalyst-controlled stereoselective cyclization reactions are demonstrated for a number of chiral substrates. DFT calculations suggest that the electronic asymmetry of the pyrox ligand synergizes with steric asymmetry to control the stereochemical outcome of the key amidopalladation step.

SUBMITTER: McDonald RI 

PROVIDER: S-EPMC3103601 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature