The reactivity of BCPIs was also explored using CO2 and CatBCl. In a reaction with CO2, a  5oxazaphosphetane species was isolated and demonstrated to be a key intermediate in the transformation of CO2 using phosphine imides. Moreover, in a reaction with CatBCl, the spontaneous heterolysis of the B-Cl bond in the BCPI-coordinated chloroborane was directly observed. This process would be thus viable as a key step in the Lewis acid-promoted generation of borenium species from chloroboranes. These results successfully provide evidence for two species that have been missing in contemporary organic chemistry. Further research on the application of BCPIs in the fields of organic and organometallic chemistry are ongoing in our group.