Catalytic Asymmetric Conjugate Addition of α‐Substituted Nitro Acetates to Nitro Olefins: Enantioselective Synthesis of Highly Substituted γ‐Lactams. Issue 8 (29th January 2013)

• Record Type: Journal Article
• Authors: Li, Ying‐Zi; Li, Fei; Tian, Ping; Lin, Guo‐Qiang
• Is Part Of: European journal of organic chemistry. Issue 8(2013)
• Page Start: 1558
• Page End: 1565
• Publication Date: 2013-01-29
• Subjects: Asymmetric catalysis -- Organo­catalysis -- Nitrogen heterocycles -- Conjugate addition -- Lactams; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.201201444
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract: Bifunctional bis(demethyldihydroquinine)‐catalyzed asymmetric conjugate addition of α‐substituted nitro acetates to nitro olefins is described. These addition reactions proceed smoothly with a low catalyst loading (1.0 mol‐%) at 0 °C, giving excellent diastereo‐ (up to 99:1 dr ) and enantioselectivities (up to 98 % ee ). Furthermore, highly substituted and optically pure 1‐pyrazoline and γ‐lactam have been prepared to demonstrate the synthetic application of the addition products. Abstract : A chiral α‐quaternary nitro acetate, a β‐tertiary carbon stereocenter, and a γ‐nitro group have been successfully constructed in one step through the catalytic asymmetric conjugate addition of α‐substituted nitro acetates to nitro olefins. Highly substituted and optically pure 1‐pyrazolines and γ‐lactams are easily accessible from the addition products.