Copper-Catalyzed Asymmetric Allylic Arylation with Grignard Reagents

Significance

The copper-catalyzed asymmetric allylic alkylation is a well-established and valuable transformation. The analogous reaction utilizing aryl nucleophiles is much less developed. The asymmetric allylic arylation reaction often suffers from low enantioselectivity and poor linear/branched ratios (Chem. Commun. 2008, 5140). The authors report a significant advancement in this field by the addition of aryl Grignard reagents to cinnamyl-like allylic halides. The chiral branched products resulting from γ-addition are formed with good yields, regioselectivity, and enantioselectivity.