Organosilanes are useful intermediates in organic synthesis and precursors for polymers. They are commonly synthesized via the catalytic hydrosilylation of alkenes. This usually requires expensive homogeneous Pt-based catalysts. Heterogeneous catalysts for this reaction that are based on cheaper metals could make the reaction more practical and cost-effective.
Xile Hu and colleagues, École Polytechnique Fédérale de Lausanne (EPFL), Switzerland, have developed the first nickel-based metal-organic framework (MOF) catalysts which promote the anti-Markovnikov hydrosilylation of alkenes. The team prepared the catalyst from 4,4′-biphenyldicarboxylic acid and NiCl2·6 H2O. The resulting MOF has a sheet-like, crystalline structure.
The Ni-based MOF was used to catalyze the hydrosilylation of a wide variety of alkenes with diphenylsilane. The desired products (pictured) were obtained in good to excellent yields with anti-Markovnikov selectivity. The catalyst is easy to remove and recycle, achieves turn-over numbers of up to 9,500, and retains good activity even after 10 uses.
- Alkene Hydrosilylation Catalyzed by Easily Assembled Ni(II)-Carboxylate MOFs,
Zhikun Zhang, Lichen Bai, Xile Hu,
Chem. Sci. 2019.
https://doi.org/10.1039/c9sc00126c