Asymmetric Catalytic 1,3-Dipolar Cycloaddition Reaction of Nitrile Imines for the Synthesis of Chiral Spiro-Pyrazoline-Oxindoles
作者:Gang Wang、Xiaohua Liu、Tianyu Huang、Yulong Kuang、Lili Lin、Xiaoming Feng
DOI:10.1021/ol303097j
日期:2013.1.4
cycloaddition of nitrile imines with 3-alkenyl-oxindoles was catalyzed by a new chiral Mg(ClO4)2 complex of an N,N′-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
新型的N,N'-二氧化物配体的手性Mg(ClO 4)2配合物催化了腈亚胺与3-烯基-氧吲哚的新的1,3-偶极环加成反应。到目前为止,该反应是螺-吡唑啉-羟吲哚衍生物的唯一催化合成。探索了多种底物以获得良好的产率(高达98%)和优异的对映选择性(高达99%)。这种环加成反应扩大了2-吡唑啉亚基结构中1,3-偶极炔丙基阴离子的范围。