Catalytic intermolecular linear allylic C-H amination via heterobimetallic catalysis

A novel heterobimetallic Pd(II)sulfoxide/(salen)Cr(III)Cl-catalyzed intermolecular linear allylic C-H amination (LAA) is reported. This reaction directly converts densely functionalized M-olefin substrates If equiv) to linear (E)-allylic carbamates with good yields and outstanding regio- and stereoselectivities (>20:1). Chiral bis-homoallylic and homoallylic oxygen, nitrogen, and carbon substituted alpha-olefins undergo allylic C-H amination with good yields, excellent selectivities, and no erosion in enantiomeric purity. Streamlined routes to (E)-allylic carbamates that can be further elaborated to medicinally and biologically relevant alylic amines are also demonstrated. Valuable N-15-labeled allylic amines may be generated directly from allo moieties at late stages of synthetic routes by using the readily available N-15-(methoxycarbonyl)-p-toluenesulfonamide nucleophile. Evidence is provided that this reaction proceeds via a heterobimetallic mechanism where Pd/sulfoxide mediates allylic C-H cleavage to form a pi-allyl Pd intermediate, and (salen)Cr(III)Cl/BQ work together to promote functionalization with the nitrogen nucleophile.