论文成果
An Organocatalytic Asymmetric Friedel-Crafts Addition/Fluorination Sequence: Construction of Oxindole-Pyrazolone Conjugates Bearing Vicinal Tetrasubstituted Stereocenters
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- 论文类型：期刊论文
- 发表时间：2015-11-06
- 发表刊物：ORGANIC LETTERS
- 收录刊物：SCIE、PubMed、Scopus
- 文献类型：J
- 卷号：17
- 期号：21
- 页面范围：5168-5171
- ISSN号：1523-7060
- 摘要：A highly efficient and practical one-pot sequential process, consisting of an organocatalytic enantioselective Friedel-Crafts-type addition of 4-nonsubstituted pyrazolones to isatin-derived N-Boc ketimines and a subsequent diastereoselective fluorination of the pyrazolone moiety, is developed. This reaction sequence delivers novel oxindole pyrazolone adducts featuring vicinal tetrasubstituted stereocenters with a 0.5 mol % catalyst loading in high yield with excellent enantio- and diastereocontrol. Notably, chloro, bromo, and thioether functionalities can be readily incorporated, rendering a broad diversity of the product.
