Revisiting the Synthetic Utility of 4,5‐Dehydro[2.2]paracyclophane

Abstract 4,5‐Dehydro[2.2]paracyclophane, an aryne species of [2.2]paracyclophane ([2.2]PCP) was reported more than half a century ago. However, despite its potential usefulness for preparing [2.2]PCP derivatives, this species is rarely considered in synthetic applications, probably because the efficiency of aryne generation and reaction with arynophiles are low under harsh reaction conditions of classical methods involving precursors. We have prepared o ‐iodoaryl triflate‐ and o ‐silylaryl triflate‐type precursors and achieved generation of 4,5‐dehydro[2.2]PCP, which reacted with a diverse range of arynophiles to afford functionalized [2.2]PCP derivatives, including [2.2]PCP‐fused π‐extended polyaromatics. Our results highlight the synthetic utility of the historically overlooked 4,5‐dehydro[2.2]PCP intermediate.