Catalytic Performance of Zr‐Based Metal–Organic Frameworks Zr‐abtc and MIP‐200 in Selective Oxidations with H<sub>2</sub>O<sub>2</sub>
Nataliya V. Maksimchuk, Irina D. Ivanchikova, Kyung Ho Cho, Olga V. Zalomaeva, Vasilii Yu. Evtushok, Kirill P. Larionov, Tatiana S. Glazneva, Jong‐San Chang, Oxana A. Kholdeeva
Abstract
Abstract The catalytic performance of Zr‐abtc and MIP‐200 metal–organic frameworks consisting of 8‐connected Zr 6 clusters and tetratopic linkers was investigated in H 2 O 2 ‐based selective oxidations and compared with that of 12‐coordinated UiO‐66 and UiO‐67. Zr‐abtc demonstrated advantages in both substrate conversion and product selectivity for epoxidation of electron‐deficient C=C bonds in α,β‐unsaturated ketones. The significant predominance of 1,2‐epoxide in carvone epoxidation, coupled with high sulfone selectivity in thioether oxidation, points to a nucleophilic oxidation mechanism over Zr‐abtc. The superior catalytic performance in the epoxidation of unsaturated ketones correlates with a larger amount of weak basic sites in Zr‐abtc. Electrophilic activation of H 2 O 2 can also be realized, as evidenced by the high activity of Zr‐abtc in epoxidation of the electron‐rich C=C bond in caryophyllene. XRD and FTIR studies confirmed the retention of the Zr‐abtc structure after the catalysis. The low activity of MIP‐200 in H 2 O 2 ‐based oxidations is most likely related to its specific hydrophilicity, which disfavors adsorption of organic substrates and H 2 O 2 .