重氮乙酸酯与缺电子烯烃的对映选择性1,3-偶极环加成反应。

Enantioselective 1,3-dipolar cycloadditions of diazoacetates with electron-deficient olefins.

作者信息

Sibi Mukund P, Stanley Levi M, Soeta Takahiro

机构信息

Department of Chemistry, North Dakota State University, Fargo, North Dakota 58105, USA.

出版信息

Org Lett. 2007 Apr 12;9(8):1553-6. doi: 10.1021/ol070364x. Epub 2007 Mar 17.

DOI:10.1021/ol070364x

PMID:17367154

Abstract

[reaction: see text] A general strategy for highly enantioselective 1,3-dipolar cycloaddition of diazoesters to beta-substituted, alpha-substituted, and alpha,beta-disubstituted alpha,beta-unsaturated pyrazolidinone imides is described. Cycloadditions utilizing less reactive alpha,beta-disubstituted dipolarophiles require elevated reaction temperatures, but still provide the corresponding pyrazolines with excellent enantioselectivities. Finally, an efficient synthesis of (-)-manzacidin A employing this cycloaddition methodology as a key step is illustrated.

摘要

[反应：见正文] 描述了一种将重氮酯与β-取代、α-取代以及α,β-二取代的α,β-不饱和吡唑烷酮酰亚胺进行高对映选择性1,3-偶极环加成反应的通用策略。使用反应活性较低的α,β-二取代亲偶极体的环加成反应需要升高反应温度，但仍能以优异的对映选择性得到相应的吡唑啉。最后，展示了以该环加成方法作为关键步骤高效合成(-)-曼扎西丁A的过程。