Simple Approach toward N-Heterocyclic Carbene-Protected Gold Nanoclusters

Jing Sun; Xiongkai Tang; Jiaqi Tang; Yuhao Zhang; Zilin Li; Chaolumen; Shuo Guo; Hui Shen

doi:10.1021/acs.inorgchem.2c04200

Simple Approach toward N-Heterocyclic Carbene-Protected Gold Nanoclusters

Inorg Chem. 2023 Apr 3;62(13):5088-5094. doi: 10.1021/acs.inorgchem.2c04200. Epub 2023 Mar 22.

Authors

Jing Sun^{1

2}, Xiongkai Tang³, Jiaqi Tang⁴, Yuhao Zhang³, Zilin Li¹, Chaolumen², Shuo Guo², Hui Shen¹

Affiliations

¹ College of Energy Materials and Chemistry, Inner Mongolia University, Hohhot 010021, China.
² Inner Mongolia Key Laboratory of Fine Organic Synthesis, Department of Chemistry and Chemical Engineering, College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021, China.
³ College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
⁴ CAS Center for Excellence in Nanoscience, Beijing Key Laboratory of Micro-nano Energy and Sensor, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 101400, China.

PMID: 36947487
DOI: 10.1021/acs.inorgchem.2c04200

Abstract

Little advance has been made toward developing alternative bottom-up synthetic strategies for N-heterocyclic carbene (NHC)-stabilized gold nanoclusters, although this unique class of nanomaterials has exhibited exciting properties. We report in this work a simple and straightforward approach toward NHC-ligated gold nanoclusters by using imidazolium salts rather than free carbenes or NHC-coordinated gold complexes (NHC-Au-X, X is counterions) as precursors. Illustrated here is a one-pot and one-step preparation of an NHC-stabilized Au₁₃Br₄ cluster that features a distinct molecular formula, surface motifs, and assembling modes via chemical reduction of dpaAu, NaOMe, and ^FNHC^Bn·HBr by NaBH₄ (Hdpa is dipyridylamine; ^FNHC^Bn·HBr is 1,3-dibenzyl-5,6-difluoro-1H-benzo[d]imidazole-3-ium bromide). In situ UV-vis and NMR studies have elucidated the base-assisted formation of NHCs from imidazolium salts for the protection of the metal core. This work not only reports a new NHC-ligated superatom that completes the Au₁₃ library, thus facilitating structure-property studies, but also opens the door to explore underlying analogues in a facile and reasonable way.