Asymmetric Catalytic 1,3-Dipolar Cycloaddition Reaction of Nitrile Imines for the Synthesis of Chiral Spiro-Pyrazoline-Oxindoles

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• 作者：Gang Wang ; Xiaohua Liu ; Tianyu Huang ; Yulong Kuang ; Lili Lin ; Xiaoming Feng
• 刊名：Organic Letters
• 出版年：2013
• 出版时间：January 4, 2013
• 年：2013
• 卷：15
• 期：1
• 页码：76-79
• 全文大小：298K
• 年卷期：v.15,no.1(January 4, 2013)
• ISSN：1523-7052

文摘

A new 1,3-dipolar cycloaddition of nitrile imines with 3-alkenyl-oxindoles was catalyzed by a new chiral Mg(ClO₄)₂ complex of an N,N鈥?dioxide ligand. The reaction is so far the sole catalytic synthesis of spiro-pyrazoline-oxindole derivatives. A wide variety of substrates were explored to obtain good yields (up to 98%) and excellent enantioselectivities (up to 99%). This cycloaddition expands the scope of propargyl anion type 1,3-dipole in the construction of 2-pyrazoline subunit.