已使用57 FeMössbauer和1 H NMR光谱研究了一系列[3]二茂铁烯(FcP)衍生物。对于在中性和酸性介质中的2-乙酰基和3-乙酰基FcP,质子共振通过与未桥接物质的类比分配,它们本身使用特定的α氘代化合物进行了分析。2-乙酰基-FcP由于羰基官能团的平面外变形而显示出强烈屏蔽的甲基。由母体醇在CF 3 CO 2 H中生成相应的碳正离子,并对其NMR光谱进行了讨论。[3]二茂铁-6,8-二酮(A)在CF 3 CO 2 H中未质子化,在80%H 2 SO 4中单质子化给出对称的碳正离子。离子的NMR光谱已得到充分讨论。2-和3-乙酰基-FcP的莫斯鲍尔光谱表明,后者的四极分裂(QS)和异构体位移(IS)都异常低。
An investigation of the formation of 1,3,5-heterosubstituted benzene rings by cyclo-condensation of acetyl-substituted organometallic complexes
作者:Francis O. Ogini、Yanick Ortin、Amir H. Mahmoudkhani、Anthony F. Cozzolino、Michael J. McGlinchey、Ignacio Vargas-Baca
DOI:10.1016/j.jorganchem.2008.02.013
日期:2008.5
The cyclocondensation of acetylferrocene and acetylcymantrene catalyzed by SiCl(4) in ethanol yields a mixture of 1,3,5-trisubstituted benzenes and the intermediate 3,1-disubstituted (E)-2-buten-1-ones, including all the homo- and heterometallic species, which were separated and quantified by HPLC. The relative yields of these species are determined by the different ability of the organometallic groups to stabilize the cationic intermediates that participate in the reaction mechanism, which is measurable as the basicity of the starting materials. The X-ray crystal structures of 1-cymantrenyl-3,5-diferrocenylbenzene and (E)-3-cymantrenyl-1-ferrocenyl-2-buten-1-one are described within this report. (C) 2008 Elsevier B.V. All rights reserved.