Superacid-Catalyzed Dimerization/Cyclization of Isopropenyl-PAHs - Novel Pathways to PAH Dimers, Phenalenes and Their Stable Carbocations
作者:Cédric Brulé、Fatima Sultana、Sandro Hollenstein、Takao Okazaki、Kenneth K. Laali
DOI:10.1002/ejoc.200800252
日期:2008.7
having four and five fused-ring systems, namely pyrene, chrysene, benzo[c]phenanthrene (BcPh), dibenzo[a,c]anthracene (benzo[f]tetraphene) and perylene, were synthesized by Wittig olefination from the corresponding acetyl-PAHs. Under the influence of triflic acid (TfOH), the isopropenyl derivatives were converted to novel PAH dimers and/or phenalenes in a simple one-pot procedure. A plausible mechanism
具有四个和五个稠环系统的多环芳烃 (PAH) 的代表性类别的异丙烯基衍生物,即芘、芘、苯并 [c] 菲 (BcPh)、二苯并 [a,c] 蒽 (苯并 [f] 四苯)和苝,是通过 Wittig 烯化从相应的乙酰基多环芳烃合成的。在三氟甲磺酸 (TfOH) 的影响下,异丙烯基衍生物通过简单的一锅法转化为新型 PAH 二聚体和/或苯。概述了该过程的合理机制,并探索了该化学的合成范围。多环芳烃二聚体的结构特征通过 DFT 检查。作为反应序列中代表性的初始和最终碳阳离子中间体,源自 3-异丙烯基苝和 4,6,6-三甲基-6H-二苯并[a, kl]蒽是通过核磁共振光谱直接产生和研究的。讨论了所得苄基碳正离子的 NMR 特性和电荷离域模式。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)