Stepwise\nSynthesis of Robust Metal–Organic\nFrameworks via Postsynthetic Metathesis and Oxidation of Metal Nodes\nin a Single-Crystal to Single-Crystal Transformation

Abstract

Utilizing <b>PCN-426-Mg</b> as a template, two robust metal-organic\nframeworks (MOFs), <b>PCN-426-Fe­(III)</b> and <b>PCN-426-Cr­(III)</b>, have been synthesized through a strategy of postsynthetic metathesis\nand oxidation (PSMO) of the metal nodes step by step. The frameworks\nremained in their single crystal form throughout. Furthermore, the\nstability and porosity of the frameworks were significantly improved\nafter PSMO. By taking advantage of both the kinetically labile metal–ligand\nexchange reactions prior to oxidation and the kinetically inert metal–ligand\nbonds after oxidation, robust MOFs, which would otherwise be difficult\nto synthesize, can be readily prepared.