Gold-Catalyzed Three-Component Annulation: Efficient Synthesis of Highly Functionalized Dihydropyrazoles from Alkynes, Hydrazines, and Aldehydes or Ketones

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• 作者：Yamato Suzuki ; Saori Naoe ; Shinya Oishi ; Nobutaka Fujii ; Hiroaki Ohno
• 刊名：Organic Letters
• 出版年：2012
• 出版时间：January 6, 2012
• 年：2012
• 卷：14
• 期：1
• 页码：326-329
• 全文大小：295K
• 年卷期：v.14,no.1(January 6, 2012)
• ISSN：1523-7052

文摘

Polysubstituted dihydropyrazoles were directly obtained by a gold-catalyzed three-component annulation. This reaction consists of a Mannich-type coupling of alkynes with N,N鈥?disubstituted hydrazines and aldehydes/ketones followed by intramolecular hydroamination. Cascade cyclization using 1,2-dialkynylbenzene derivatives as the alkyne component was also performed producing fused tricyclic dihydropyrazoles in good yields.