Department of Chemistry, Illinois State University , Normal, Illinois 61790-4160, United States.
J Org Chem. 2013 Sep 20;78(18):9143-52. doi: 10.1021/jo401365p. Epub 2013 Sep 3.
Benzitripyrranes were prepared by reacting diphenyl-substituted benzenedicarbinols with excess pyrrole in the presence of BF3·Et2O. These dipyrrolic compounds underwent acid-catalyzed condensations with a pyrrole dialdehyde to afford good yields of diphenylbenziporphyrins, and further reaction with palladium(II) acetate gave stable organometallic derivatives. The X-ray crystal structure of a palladium(II) benziporphyrin showed that the system deviates significantly from planarity. Although the benzitripyrranes failed to give stable macrocyclic products with furan or thiophene dialdehydes, they afforded tetraphenyl heterobenziporphyrins upon reaction with diphenyl-substituted furan- or thiophenedicarbinols and BF3·Et2O. Benziporphyrins and their heteroanalogues showed no indication of a diamagnetic ring current by proton NMR spectroscopy, but addition of TFA gave rise to the formation of weakly diatropic dications.
苯并三吡咯烷通过二苯基取代的苯二甲醛与过量吡咯在 BF3·Et2O 的存在下反应制备。这些二吡咯化合物在酸催化下与吡咯二醛缩合，得到高产率的二苯基苯并卟啉，进一步与醋酸钯反应得到稳定的有机金属衍生物。钯(II)苯并卟啉的 X 射线晶体结构表明，该体系明显偏离平面。尽管苯并三吡咯烷未能与呋喃或噻吩二醛生成稳定的大环产物，但它们与二苯基取代的呋喃或噻吩二醛醇和 BF3·Et2O 反应得到四苯基杂苯并卟啉。苯并卟啉及其杂类似物通过质子 NMR 光谱没有显示出反磁环电流的迹象，但加入 TFA 会导致弱的外向二阳离子的形成。
