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Updated: Feb 24, 2026

Author Spotlight: Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers
Published on: May 12, 2023
Bidentate Phosphine-Assisted Synthesis of an All-Alkynyl-Protected Ag74 Nanocluster
Mei Qu1, Huan Li1, Lin-Hua Xie2
1Institute of Crystalline Materials, Shanxi University , Taiyuan 030006, Shanxi, China.
Abstract:
Determining the total structure of metal nanoparticles is vital to understand their properties. In this work, the first all-alkynyl-protected Ag nanocluster, Ag74(C≡CPh)44, was synthesized and structurally characterized by single crystal diffraction. Ag atoms are arranged in a Ag4@Ag22@Ag48 three shell structure and all 44 phenylethynyl ligands coordinated with Ag in a μ3 mode. In spite of being absent in nanocluster, 31P NMR study reveals that bidentate phosphine first reacts with Ag(I) to form a dinuclear complex, from which Ag atoms are then released to phenylethynyl ligands. This phosphine mediated strategy may find general application in synthesis of alkynyl-protected Ag nanoclusters.
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Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
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