Copper(I)‐Catalyzed Asymmetric Allylation of Ketones with 2‐Aza‐1,4‐Dienes

• Published in: Angewandte Chemie 2024-01, Vol.136 (1), p.n/a
• Main Authors: Pan, Zhi‐Zhou, Li, Jia‐Heng, Tian, Hu, Yin, Liang
• Format: Article
• Language: English
• Subjects: Alcohols; Allyl compounds; Allylation; Asymmetric Catalysis; Asymmetric synthesis; Asymmetry; Chemical reactions; Chemistry; Copper; Copper Catalysis; Dienes; Enantiomers; Ketone; Ketones; Proton-Transfer
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.202315293

Catalytic asymmetric allylation of ketones under proton‐transfer conditions is a challenging issue due to the limited pronucleophiles and the electrophilic inertness of ketones. Herein, a copper(I)‐catalyzed asymmetric allylation of ketones with 2‐aza‐1,4‐dienes (N‐allyl‐1,1‐diphenylmethanimines) is disclosed, which affords a series of functionalized homoallyl tertiary alcohols in high to excellent enantioselectivity. Interestingly, N‐allyl‐1,1‐diphenylmethanimines work as synthetic equivalents of propanals. Upon the acidic workup, a formal asymmetric β‐addition of propanals to ketones is achieved. An investigation on KIE effect indicates that the deprotonation of N‐allyl‐1,1‐diphenylmethanimines is the rate‐determining step, which generates nucleophilic allyl copper(I) species. Finally, the synthetic utility of the present method is demonstrated by the asymmetric synthesis of (R)‐boivinianin A and (R)‐gossonorol. A copper(I)‐catalyzed asymmetric allylation of ketones with 2‐aza‐1,4‐dienes (N‐allyl‐1,1‐diphenylmethanimines) is disclosed, which affords a series of functionalized homoallyl tertiary alcohols in high to excellent enantioselectivity.