New strategies for the design and synthesis of novel covalent organic frameworks (COFs) and related materials
Final Report Abstract
Covalent organic frameworks (COFs) represent a vastly emerging class of two- and three dimensional organic materials and have inspired the imagination of researchers due to their extra-large surface areas and very low density, resulting in many potential applications. The directionality and rigidity of organic molecular building units, joined together by covalent bonds, have made these extended nets particularly attractive from a design perspective. COFs show order with atomic precision and can therefore be modified with a versatility, unparalleled in traditional polymer materials. However, only a handful of covalent bond formation reactions have been utilized thus far in context of COFs. We herein aimed on a de-novo material design and synthesis approach involving mechanically bonded macrocyclic structures. The design and structure simulations were carried out using well known small molecules as building units and stitched them together computationally. The synthetic challenge was approached from three different pathways, including preformed building blocks, a hierarchical self-assembly strategy and a 2-step synthesis with subsequent photoreaction. We were finally able to isolate a material with a high level of complexity, given the simple reactants. A hierarchical assembly of [4+4] macrocycle into dimers, and subsequent crystallization, produced a compound with square nanopores. The crystal structure of these materials is strongly dependent on the packing of the dimers in ABAB or related fashion.
Publications
- Porosity in Metal-Organic Compounds. Macrocyclic and Supramolecular Chemistry: How Izatt-Christensen Award Winners Shaped the Field (R. M. Izatt, Ed.), Wiley-VCH, Weinheim, 2016
Schoedel A., Yaghi O. M.
- Reticular Chemistry of Metal-Organic Frameworks Composed of Copper and Zinc Metal-Oxide Secondary Building Units as Nodes. The Chemistry of Metal-Organic Frameworks. Synthesis, Characterization and Applications (S. Kaskel, Ed.), Wiley-VCH, Weinheim, Vol. 2, 2016
Schoedel A., Yaghi O. M.
- The role of metal-organic frameworks in a carbon-neutral energy cycle. Nat. Energy 2016, 1, 16034-16046
Schoedel A., Ji Z., Yaghi O. M.
(See online at https://doi.org/10.1038/NENERGY.2016.34) - Two Principles of Reticular Chemistry Uncovered in a Metal-Organic Framework of Heterotritopic Linkers and Infinite Secondary Building Units. J. Am. Chem. Soc. 2016, 138, 10826-10829
Catarineu, N. R., Schoedel A., Urban, P., Morla, M. B., Trickett, C. A., Yaghi O. M.
(See online at https://doi.org/10.1021/jacs.6b07267)