Weak Coordination Bond of Chloromethane: A Unique Way to Activate Metal Node Within an Unstable Metal–Organic Framework DUT-34

Activation of metal nodes in metal–organic frameworks (MOFs) has been viewed as an essential step prior to their use for various potential applications. So far, a thermal method has been most commonly employed for the activation despite its negative influence on the structural integrity of MOFs. Meanwhile, DUT-34 has been considered as an ideal platform for the above applications due to its open-metal sites (OMSs) at the Cu node. However, the activation of DUT-34 has not been successful because of its fragile characteristics. In this article, we report the coordination-chemistry-controlled activation, namely chemical route activation, using chloromethanes. By monitoring the coordination exchangeability of chloromethanes, we demonstrate that the chloromethanes can weakly coordinate at the OMSs. Further, we demonstrate that this coordination exchange is a safe activation method to retain the framework structure of DUT-34, based on the observation that the DUT-34 placed in TCM remained intact over 2 months.