Study of tribenzo[ <i>b</i> , <i>d</i> , <i>f</i> ]azepine as donor in D–A photocatalysts

Since the discovery of donor-acceptor (D-A) type molecules in the field of materials science, they have found great applicability in the field of photocatalysis. Most of these compounds are based on complex D-A-D structures or multi-D-A systems, such as 4CzIPN. Whereas these systems have been widely studied and applied as photocatalysts, simpler D-A structures remain less explored. Nevertheless, the simplicity of D-A structures makes them the ideal structures to further understand the structure-property relationship of D-A molecules for optimizing their photocatalytic performance by simpler modification of the different D-A subunits. In particular, D-A structures featuring sulfur-based acceptors and nitrogen donors have gained increasing attention for their use as photoredox catalysts. This study introduces a new family of D-A molecules by exploring various sulfur-based acceptors and nitrogen donors, including a novel tribenzo[<i>b,d,f</i>]azepine (TBA) unit and 5<i>H</i>-dibenz[<i>b,f</i>]azepine (IMD). Our findings demonstrate that these simple D-A structures exhibit promising photocatalytic properties, comparable to those of more complex D-A-D systems.