Qin Zhaoxian, Sharma Sachil, Wan Chong-Qing, Malola Sami, Xu Wen-Wu, Häkkinen Hannu, Li Gao
Beijing Key Laboratory for Optical Materials and Photonic Devices, Department of Chemistry, Capital Normal University, Beijing, 100048, China.
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P. R. China.
Angew Chem Int Ed Engl. 2021 Jan 11;60(2):970-975. doi: 10.1002/anie.202011780. Epub 2020 Nov 20.
A new alkynylated cluster [Au Ag (C H NO) ] is prepared by a NaBH mediated reduction method. The AuAg clusters are confirmed by sophisticated characterization techniques. It has a unique "Au @Ag @Au Ag " metal framework which is protected by 24 atypical alkyne ligands L (L=C H NO). The ligands construct a unique type of motif L-(Ag)-Au-(Ag)-L at the cluster interface, where the alkyne (C≡C) group of each L was linked by sharing an Au atom through the σ bonds and each C≡C group was discretely connected to a chemically different Ag atom (Ag /Ag ) through π bonds. The electronic and optical properties of [Au Ag L ] were studied. DFT characterized the cluster as a clear 8-electron superatom, and peaks in the optical absorption spectrum were interpreted in terms of the P and D superatom states. The supported Au Ag L /CeO catalyst exhibited high catalytic activity and selectivity towards the A -coupling reaction involving benzaldehyde, diethylamine, and phenylacetylene.
通过NaBH介导的还原方法制备了一种新的炔基化簇合物[Au Ag (C H NO) ]。通过先进的表征技术对AuAg簇合物进行了确认。它具有独特的“Au @Ag @Au Ag ”金属框架,该框架由24个非典型炔基配体L(L = C H NO)保护。这些配体在簇合物界面构建了一种独特类型的基序L-(Ag)-Au-(Ag)-L,其中每个L的炔基(C≡C)基团通过σ键共享一个Au原子相连,并且每个C≡C基团通过π键与化学性质不同的Ag原子(Ag /Ag )离散连接。研究了[Au Ag L ]的电子和光学性质。密度泛函理论(DFT)将该簇合物表征为清晰的8电子超原子,并且根据P和D超原子态对光吸收光谱中的峰进行了解释。负载型Au Ag L /CeO催化剂对涉及苯甲醛、二乙胺和苯乙炔的A -偶联反应表现出高催化活性和选择性。