Palladium‐Catalyzed Cascade sp² C−H Functionalization/Intramolecular Asymmetric Allylation: From Aryl Ureas and 1,3‐Dienes to Chiral Indolines

Abstract

A chiral PdII‐catalyzed cascade sp2 C−H functionalization/intramolecular asymmetric allylation reaction is reported. A new chiral sulfoxide–oxazoline (SOX) ligand bearing single chiral center on the sulfur was identified as the optimal ligand for the reaction, being efficient both in the C−H cleavage step and the stereocontrol of the allylation step. The broad scope of this method with respect to aryl ureas and 1,3‐dienes enables the rapid construction of valuable chiral indoline derivatives with high yields and enantioselectivities (up to 99 % yield, up to 95:5 e.r.).

Asymmetric cascades of the π-allyl complex: a journey from transition-metal catalysis to metallaphotocatalysis

“…The reaction involved the treatment of N -acetyl anilines 45a with 1,3-dienes 45b in the presence of 10 mol% of Pd-salt and 12 mol% of chiral SOX-ligand to furnish enantiomerically enriched indolines 45c in good yield and excellent enantioselectivity (Scheme 45). 76 In general, in the case of mono-substituted E -alkene, excellent selectivity was observed. However, di-substituted olefins resulted in the formation of E / Z isomers in moderate selectivity.…”