Stereoselective Tandem Cascade Furan Cycloadditions

Oligofurans linked by a rigid tether undergo tandem cycloaddition reactions with high stereoselectivity. The reaction of bisfurans with dimethyl acetylenedicarboxylate (DMAD) involves tandem [4 + 2]/[4 + 2] cycloadditions in a pincer mode. The reaction of oligofurans with arynes involves stereoselective tandem [4 + 2]/[4 + 2] cycloaddition reactions in a domino mode. The corresponding aryne adducts have been transformed into extended perylene derivatives by deoxygenation and aromatization with HCl/EtOH.

由刚性连接臂连接的低聚呋喃可发生具有高度立体选择性的串联环加成反应。双呋喃与乙酰二羧酸二甲酯（dimethyl acetylenedicarboxylate, DMAD）的反应以钳式模式进行串联[4+2]/[4+2]环加成反应。低聚呋喃与芳炔的反应则以多米诺模式发生具有立体选择性的串联[4+2]/[4+2]环加成反应。所得芳炔加合物可通过HCl/EtOH体系进行脱氧与芳构化反应，转化为拓展型苝衍生物。