Concise Synthesis of Halogenated Chrysenes ([4]Phenacenes) that Favor π-Stack Packing in Single Crystals

A concise synthesis of halogenated chrysene derivatives from 2,2,2-trifluoroethyl tosylate and halostyrene was established. Friedel−Crafts type cyclization of a 1,1-difluoro-1-alkene bearing halogenated phenyl moieties involved skeletal rearrangement and dehydrogenation to afford the title compound in good to moderate yield. X-ray analysis revealed that the halogen substituents induce π-stack packing of the molecules in the crystals.本研究建立了以对甲苯磺酸-2,2,2-三氟乙酯与卤代苯乙烯为原料，简洁合成卤代屈衍生物的方法。含卤代苯基的1,1-二氟-1-烯烃经傅-克型环化过程，伴随骨架重排与脱氢反应，最终以良好至中等收率得到标题化合物。X射线衍射分析表明，卤代取代基可诱导晶体中分子形成π堆积排列。