Copper‐Catalyzed Asymmetric Allylic Alkylation of Racemic Cyclic Allyl Bromides with Organolithium Compounds. Issue 34 (7th September 2022)

• Record Type: Journal Article
• Authors: Li, Jun; Song, Xiao; Wu, Fusong; You, Hengzhi; Chen, Fen‐Er
• Is Part Of: European journal of organic chemistry. Volume 2022:Issue 34(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-09-07
• Subjects: Alkylation -- Allylation -- Chiral phosphoramidites -- Copper -- Organolithium reagents; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.202200860
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract: Organolithium reagents are one of the most widely used reagents in chemical synthesis. Herein, we reported the first study of organolithium reagents used in asymmetric allylic alkylation (AAA) reactions with racemic cyclic substrates. A simple and efficient Cu‐catalyzed synthesis of enantiomerically enriched cycloalkene derivatives from various racemic cyclic allylic bromides was developed. The standard method employed 5 % CuBr⋅SMe2 in combination with phosphoramidite ligand L2 in DCM. Meanwhile, transfer of the reactions into flow condition for more convenient application was also studied. This new Cu‐catalyzed protocol was speculated to undergo an enantioconvergent transformation mechanism here. Abstract : Cu‐catalyzed AAA reactions employing racemic cyclic allylic bromide and extremely reactive organolithium reagents as reaction partners have been disclosed. The corresponding alkylated products were obtained with high enantioselectivities (up to 98 % ee ).