Metalation of a thiocatechol-functionalized Zr(IV)-based metal-organic framework for selective C-H functionalization

The incorporation of 2,3-dimercaptoterephthalate (thiocatecholate, tcat) into a highly robust UiO-type metal-organic framework (MOF) has been achieved via postsynthetic exchange (PSE). The anionic, electron-donating thiocatecholato motif provides an excellent platform to obtain site-isolated and coordinatively unsaturated soft metal sites in a robust MOF architecture. Metalation of the thiocatechol group with palladium affords unprecedented Pd-mono(thiocatecholato) moieties within these MOFs. Importantly, Pd-metalated MOFs are efficient, heterogeneous, and recyclable catalysts for regioselective functionalization of sp(2) C-H bond. This material is a rare example of chelation-assisted C-H functionalization performed by a MOF catalyst.