Cinchona Alkaloid Amide Catalyzed Enantioselective Formal [2+2] Cycloadditions of Allenoates and Imines: Synthesis of 2,4-Disubstituted Azetidines
作者:Jean-Baptiste Denis、Géraldine Masson、Pascal Retailleau、Jieping Zhu
DOI:10.1002/anie.201100706
日期:2011.5.27
Mix and go: The quinidine amide 1 catalyzed [2+2] cycloaddition between N‐sulfonylimines 2 and alkyl 2,3‐butadienoates 3 afforded the R‐configured azetidines 4 in excellent yields and enantioselectivities (M.S.=molecular sieve). The S enantiomer was obtained when a quinine amide catalyst, the pseudoenantiomer of 1, was used.
混合和去:酰胺的奎尼丁1催化[2 + 2]环加成之间Ñ -sulfonylimines 2和烷基2,3- butadienoates 3得到ř -构型氮杂环丁烷4以优良产率和对映选择性(MS =分子筛)。该小号奎宁酰胺催化剂,的pseudoenantiomer时得到对映异构体1,而使用。