We report herein the synthesis and full spectroscopic characterization of two A2B-corrole phosphonic acids. Thanks to the presence of a phosphonic acid functional group at the 10-meso-position, the corroles were covalently linked to the hexanuclear Zr clusters of a PCN-222 metal-organic framework (MOF). After the insertion of cobalt into the corrole macrocycle, the metal complexes are able to bind small volatile molecules such as carbon monoxide (CO). Interestingly, the resulting doped porous materials were used for selective detection of CO, with excellent selectivity for CO vs. CO2, N2, and O2.