Metal–Organic Framework Nodes as Nearly Ideal Supports for Molecular Catalysts: NU-1000- and UiO-66-Supported Iridium Complexes

• Published in: Journal of the American Chemical Society Vol. 137; no. 23; pp. 7391 - 7396
• Main Authors: Yang, Dong, Odoh, Samuel O, Wang, Timothy C, Farha, Omar K, Hupp, Joseph T, Cramer, Christopher J, Gagliardi, Laura, Gates, Bruce C
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 17.06.2015; American Chemical Society (ACS)
• Subjects: absorption; catalysis (heterogeneous), materials and chemistry by design, synthesis (novel materials); catalysts; catalytic activity; coordination polymers; dimerization; ethylene; hydrogenation; iridium; methodology; X-radiation
• ISSN: 0002-7863; 1520-5126; 1520-5126
• DOI: 10.1021/jacs.5b02956

Metal–organic frameworks with Zr6 nodes, UiO-66 and NU-1000, were investigated as supports for Ir­(CO)2 and Ir­(C2H4)2 complexes. A single bonding site for the iridium is identified on the nodes of NU-1000, whereas two sites are identified on UiO-66, although at low iridium loadings only one site is occupied. Density functional theory calculations provide structural results that are in good agreement with infrared and X-ray absorption fine-structure spectra. The reactivity of node-supported Ir­(CO)2 with C2H4 and the catalytic activity and selectivity of the species initially present as Ir­(C2H4)2 for ethylene hydrogenation and dimerization were investigated both experimentally and computationally and shown to be strongly influenced by the node.