At least this post makes me feel a little better with my confusion, as I've been thinking the same thing you said. These are a class of molecules I've been conducting research on during my undergraduate studies. I've been focused on the synthesis portion, but they are proposed to be used as redox mediators (although we've just started to get into testing their properties through cyclic voltammetry). The only source I was given at the start of the research was this paper by Hill Harmon: NHC-Stabilized Boranthrene as a Metal-Free Platform for the Activation
of Small Molecules
Jordan W. Taylor, Alex McSkimming, Camilo F. Guzman, and W. Hill Harman*
Department of Chemistry, University of California, Riverside, California 92521, United States
As well as a previous lab notebook detailing the synthesis
If you're wondering what I need the info for, I emailed my professor and asked him to help me summarize these reactions and class of molecules for updating my resume. And he wasn't much help so I came here for answers. Thanks!