Atomically Precise Metal Nanoclusters as Single Electron Transferers for Hydroborylation
Wanli Zhu1,2, Sheng Zhang1,2, Weigang Fan1,2
1Institute of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, P. R. China.
Abstract:
The emergence of metal nanoclusters with atomically precise compositions and structures provides an opportunity for in-depth investigation of catalysis mechanisms and structure-property correlations at the nanoscale. However, a serious problem for metal nanocluster catalysts is that the ligands inhibit the catalytic activity through deactivating the surface of the nanoclusters. Here, we introduce a novel catalytic mode for metal nanoclusters, in which the nanoclusters initiate the catalysis via single electron transfer (SET) without destroying the integrity of nanoclusters, providing a solution for the contradiction between activity and stability of metal nanoclusters. We illustrated that the novel activation mode featured low catalyst loading (0.01 mol %), high TOF, mild reaction conditions, and easy recycling of catalyst in alkyne hydroborylation, which often suffered from poor selectivity, low functional group tolerance, etc. Furthermore, the catalyst [Au1Cu14(TBBT)12(PPh3)6]+ (TBBTH: p-tert-butylthiophenol) can be applied in highly efficient tandem processes such as hydroborylation-deuteration and hydroborylation-isomerization, demonstrating the utility of the introduced activation mode for metal nanoclusters.
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