[Cu8(μ4-H){S2P(OEt)2}6](PF6): A Novel Catalytic Hydride-Centered Copper Cluster for Azide-Alkyne Cycloaddtion

• Published in: Catalysis letters Vol. 143; no. 6; pp. 572 - 577
• Main Authors: Lee, Bo-Han, Wu, Cheng-Chieh, Fang, Xuan, Liu, C. W., Zhu, Jia-Liang
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.06.2013; Springer Nature; Springer; Springer Nature B.V
• Subjects: Alkynes; Ambient temperature; Azides (organic); Catalysis; Catalysts; Chemistry; Chemistry and Materials Science; Chemistry, Physical; Clusters; Copper; Cycloaddition; Dimethylformamide; Exact sciences and technology; General and physical chemistry; High temperature; Hostages; Hydrides; Hydrogen; Hydrogen storage; Industrial Chemistry/Chemical Engineering; Organometallic Chemistry; Physical Chemistry; Physical Sciences; Science & Technology; Sulfur compounds; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Triazoles; 1,3-Dipolar cycloaddition; Copper(I) cluster; Click chemistry; Triazoles; Alkynes; 1,3-DIPOLAR CYCLOADDITIONS; MECHANISM; LIGATION; TERMINAL ALKYNES; ORGANIC AZIDES; 3+2 CYCLOADDITION; COPPER(I)-CATALYZED CYCLOADDITION; SCIENCE; EFFICIENT; Azides; Catalytic reaction; Acetylenic compound; Hydrocarbon; Copper I; Hydrides; Alkyne
• ISSN: 1011-372X; 1572-879X
• DOI: 10.1007/s10562-013-0993-7

A hydride-centered dithiophosphate cluster [Cu 8 (μ 4 -H){S 2 P(OEt) 2 } 6 ](PF 6 ) ( 1 )] previously developed by us was applied as a new catalyst to the 1,3-dipolar cycloaddition of organic azides and alkynes for preparing substituted trizoles. With the required catalyst loading as low as 0.4 mol%, the reactions of terminal alkynes with BnN 3 all proceeded smoothly at ambient temperature in CH 3 CN to exclusively produce 1,4-triazoles in good yields. For these reactions, it is assumed that the formation of the requisite copper acetylide intermediate is facilitated by the abstraction of the terminal hydrogen of alkynes by the hydride released from the central of the cluster. With only few examples being documented in literatures, the reactions of a range of internal alkynes have also been realized under the catalysis of 1 (0.8 mol%) in DMF at elevated temperature, to yield 1,4,5-trisubstituted triazoles in moderate to high yields. Our study has provided a preliminary insight into the effect of sulfur-based ligands on the activity of copper ion. Graphical Abstract