virtually quantitative yield by a thermally-induced extrusion of the phosphorus-containing bridge from appropriately substituted 2-phosphabicyclo[2.2.2]octa-5,7-dienes. The phosphaethenes so formed, the simplest yet produced by conventional methods, are trapped readily in [2+4] cycloadditions with conjugated dienes.
P-
甲基-和P-
苯基
磷乙烯是在溶液中,在非常温和的条件下,通过适当诱导的2-
磷双环[2.2.2] octa-5,7-二
烯的热诱导挤出含
磷桥键而以定量定量收率生成的。如此形成的膦
烯,最简单的通过常规方法生产的膦,容易被共轭二
烯捕获在[2 + 4]环加成中。