A1 Journal article (refereed)
Highly Robust but Surface-Active : An N-Heterocyclic Carbene-Stabilized Au25 Nanocluster (2019)

Shen, H., Deng, G., Kaappa, S., Tan, T., Han, Y.-Z., Malola, S., Lin, S.-C., Teo, B. K., Häkkinen, H., & Zheng, N. (2019). Highly Robust but Surface-Active : An N-Heterocyclic Carbene-Stabilized Au25 Nanocluster. Angewandte Chemie, 58(49), 17731-17735. https://doi.org/10.1002/anie.201908983

JYU authors or editors

Publication details

All authors or editors: Shen, Hui; Deng, Guocheng; Kaappa, Sami; Tan, Tongde; Han, Ying-Zi; Malola, Sami; Lin, Shui-Chao; Teo, Boon K.; Häkkinen, Hannu; Zheng, Nanfeng

Journal or series: Angewandte Chemie

ISSN: 1433-7851

eISSN: 1521-3773

Publication year: 2019

Volume: 58

Issue number: 49

Pages range: 17731-17735

Publisher: Wiley-VCH Verlag

Publication country: Germany

Publication language: English

DOI: https://doi.org/10.1002/anie.201908983

Publication open access: Not open

Publication channel open access: 

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/67174

Abstract

Surface organic ligands play a critical role in stabilizing atomically precise metal nanoclusters in solutions. However, it is still challenging to prepare highly robust ligated metal nanoclusters that are surface-active for liquid-phase catalysis without any pre-treatment. Now, an N-heterocyclic carbene-stabilized Au25 nanocluster with high thermal and air stabilities is presented as a homogenous catalyst for cycloisomerization of alkynyl amines to indoles. The nanocluster, characterized as [Au25(iPr2-bimy)10Br7]2+ (iPr2-bimy=1,3-diisopropylbenzimidazolin-2-ylidene) (1), was synthesized by direct reduction of AuSMe2Cl and iPr2-bimyAuBr with NaBH4 in one pot. X-ray crystallization analysis revealed that the cluster comprises two centered Au13 icosahedra sharing a vertex. Cluster 1 is highly stable and can survive in solution at 80 °C for 12 h, which is superior to Au25 nanoclusters passivated with phosphines or thiols. DFT computations reveal the origins of both electronic and thermal stability of 1 and point to the probable catalytic sites. This work provides new insights into the bonding capability of N-heterocyclic carbene to Au in a cluster, and offers an opportunity to probe the catalytic mechanism at the atomic level.

Keywords: nanoparticles; gold; catalysts; catalysis

Free keywords: Au25; carbene ligands; gold catalysis; gold nanoclusters; homogeneous catalysis

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2019

JUFO rating: 3