An efficient access to tetrahydrofuran‐fused bicyclo[2.2.2]oct‐2‐enes via palladium‐catalyzed cyclization of oxygen‐tethered 2,7‐alkadiynylic carbonates with 2‐(buta‐2,3‐dienyl)malononitrile has been developed. Perfect chiral induction was observed when a substituent was introduced to the propargylic position affording the optically active polycyclic products of both enantiomers. Control experiments showed that the oxygen tether of 2,7‐alkadiynylic carbonates and the two cyano groups in allene are indispensible for this transformation.

中文翻译：

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四氢呋喃双环[2.2.2] oct-2-烯的丙二烯方法

通过钯催化氧连接的2,7-链二炔碳酸酯与2-（buta-2,3-dienyl）丙二腈的钯催化环化反应，可以有效地获得四氢呋喃稠合的双环[2.2.2] oct-2-烯。当将取代基引入炔丙基位置时，观察到完美的手性诱导，提供两种对映体的光学活性多环产物。对照实验表明，2,7-链二炔碳酸酯的氧链和艾伦中的两个氰基对于该转化是必不可少的。