Highly Regioselective Synthesis of Multisubstituted Pyrroles via Ag-Catalyzed [4+1C]<sup>insert</sup> Cascade
作者:Kaixiu Luo、Shuai Mao、Kun He、Xianglin Yu、Junhong Pan、Jun Lin、Zhihui Shao、Yi Jin
DOI:10.1021/acscatal.9b05360
日期:2020.3.20
C–C bond carbenoid formal insertion/cyclization/[1,5]-shift cascade reaction was successfully developed, providing distinct chemo- and regioselective multisubstituted pyrroles. The plausible reaction mechanism involves two catalytic cycles: in the first one, silver ions regioselectively catalyze the C–C bond formal insertion reaction; in the second one, silver ions chemo- and regioselectively control
成功开发了一种有效的[4 + 1C]插入方法,通过AgOTf催化的C–C键类胡萝卜素正式插入/环化/ [1,5]-移位级联反应将烯胺酮与供体/受体或供体/供体碳烯偶联。提供不同的化学和区域选择性多取代吡咯。可能的反应机理涉及两个催化循环:在第一个催化循环中,银离子区域选择性催化C–C键形式插入反应;在第二个中,银离子化学和区域选择性地控制环化和[1,5]转移反应。该方法不仅为多取代吡咯的合成提供了便利,并在多价吡咯的合成中应用了原子经济性,而且为通过简便修饰所得4 H进一步实现吡咯多样化提供了切入点。-吡咯产物,如天然产物lamellarin L的简短形式合成所示。