Synthesis and structure of novel ferrocene-containing β-carbolines including polycondensed derivatives with the elements of planar-, central- and conformational chirality

摘要

Employing tryptamine or tryptophane methylester hydrochloride and (Sp)-2-formylferrocene-1-udcarboxylate as precursors by means of PicteteSpengler reactions and subsequent intramolecular acylationudeffected by cyanuricfluoride or carbonyldiimidazole (CDI), the first representatives of ferrocenecontainingudb-carboline derivatives including polycyclic ferroceno/fused lactames, were prepared. In theudcourse of CDI-mediated tandem cyclization of a tryptophane-derived carboxyferrocenyl-substituted bcarboline,uda ring enlargement simultaneously taking place with the loss of the h5-C5H5Feþ fragment ofudthe fused ferrocene moiety, effected by the coordinating imidazole released from the reagent, led to a 4Hcyclopenta[ud7,8]azonino[5,4-b]indole as a minor product. The constitution and relative configuration ofudthe new compounds with the elements of planar-, central- and conformational chirality were establishedudby NMR methods including HMQC, HMBC and NOESY measurements supported by DFT modelingudstudies.ud