Regioselective addition/annulation of ferrocenyl thioamides with 1,3-diynes <i>via</i> a sulfur-transfer rearrangement to construct extended π-conjugated ferrocenes with luminescent properties
Lipeng Yan, Jingbo Lan, Cheng Hu, Yihang Li, Mangang Zhang, Di Wu, Jingsong You
Abstract
-C-H bond of the ferrocene, but also as a sulfur source to form the thiophene ring. The resulting carboxylic ester group after sulfur transfer can act as a linkage to construct extended π-conjugated ferrocenes (OCTFc) with luminescent properties. ThienylFc displays effective fluorescence quenching due to the photoinduced electron transfer (PET) from the Fc unit to the excited luminophore, which turns out to be a promising type of redox molecular switch. OCTFc exhibit relatively strong emission owing to their intramolecular charge transfer (ICT) characteristics. The ring-fused strategy is herein employed for the first time to construct luminescent materials based on ferrocenes, which provides inspiration for the development of novel organic optoelectronic materials, such as electroluminescent materials based on ferrocenes.