365567-24-4Relevant academic research and scientific papers
Ring-Strain-Enabled Catalytic Asymmetric Umpolung C-O Bond-Forming Reactions of 1,2-Oxazetidines for the Synthesis of Functionalized Chiral Ethers
Wu, Binyu,Yang, Jinggang,Gao, Min,Hu, Lin
supporting information, p. 5561 - 5566 (2020/07/14)
An unprecedented catalytic asymmetric umpolung C-O bond-forming reaction of N-nosyl 1,2-oxazetidines with β-keto esters has been achieved in the presence of a chiral phase-transfer catalyst, allowing access to a range of highly functionalized chiral ethers bearing quaternary and no adjacent stereogenic centers with high yields, excellent enantioselectivities, and diastereoselectivities (up to 97percent ee and 20:1 dr). These versatile products could be flexibly transformed into biologically important chiral fused and spiro morpholines in two steps.
Asymmetric α-alkylation of cyclic β-keto esters and β-keto amides by phase-transfer catalysis
Wang, Yakun,Li, Yueyun,Lian, Mingming,Zhang, Jixia,Liu, Zhaomin,Tang, Xiaofei,Yin, Hang,Meng, Qingwei
supporting information, p. 573 - 584 (2019/01/24)
Without employing any transition metal, a highly enantioselective α-alkylation of cyclic β-keto esters and β-keto amides has been realized by phase-transfer catalysis. This improved procedure is applicable to different kinds of halides with cinchona derivatives and gives the corresponding products in excellent enantiopurities (up to 98% ee) and good yields (up to 98%). Moreover, the reaction was scalable and the phase-transfer catalyst was recyclable. This provided an alternative and competitive method to the asymmetric α-alkylation of β-dicarbonyl compounds.
Asymmetric direct α-hydroxylation of β-Oxo esters by phase-transfer catalysis using chiral quaternary ammonium salts
Lian, Mingming,Li, Zhi,Du, Jian,Meng, Qingwei,Gao, Zhanxian
supporting information; experimental part, p. 6525 - 6530 (2011/02/25)
The first enantioselective direct α-hydroxylation of β-oxo esters was developed by using phase-transfer catalysis. 1-Indanone-derived 1-adamantyl (1-Ad) β-oxo esters, in the presence of commercially available cumyl hydroperoxide and a cinchonine-based ammonium salt, resulted in the corresponding products with 69-91 % yield and 65-74 % ee. The reaction had also been successfully scaled-up to a gram quantity, and a similar yield was obtained without loss of the enantioselectivity. Copyright
