title: Organocatalytic asymmetric conjugate addition and cascade acyl transfer reaction of α-nitroketones.
abstract: Organocatalytic asymmetric conjugate addition of α-nitroketones to β,γ-unsaturated α-keto esters has been developed. A pyrrolidine-based thiourea-tertiary amine was identified as the best catalyst. The reaction was found to proceed via cascade conjugate addition and acyl transfer reaction. A number of α-nitroketones and β,γ-unsaturated α-keto esters were examined in this transformation. 5-Nitro-2-acyloxypent-2-enoates were obtained in good yields (up to 99%) and enantioselectivities (up to 99% ee). The products could be hydrolyzed to provide 5-nitro-2-oxopentanoates, which are not available from the direct addition of nitromethane to β,γ-unsaturated α-keto esters.
authors.affiliation: Institute of Drug Synthesis and Pharmaceutical Process, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
authors.forename: Rui-jiong
authors.initials: RJ
authors.lastname: Lu
authors.forename: Yun-yun
authors.initials: YY
authors.lastname: Yan
authors.forename: Jin-jia
authors.initials: JJ
authors.lastname: Wang
authors.forename: Quan-sheng
authors.initials: QS
authors.lastname: Du
authors.forename: Shao-zhen
authors.initials: SZ
authors.lastname: Nie
authors.forename: Ming
authors.initials: M
authors.lastname: Yan
mesh_terms: D000588:Amines / Q000737:chemistry*; D002384:Catalysis; D018360:Crystallography, X-Ray; D004952:Esters; D007659:Ketones / Q000737:chemistry*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D015394:Molecular Structure; D009574:Nitro Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D009595:Nitroparaffins / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000588:Amines; D004952:Esters; D007659:Ketones; D009574:Nitro Compounds; D009595:Nitroparaffins; D008697:Methane; C008640:nitromethane