Heterothiometallic clusters as robust and efficient copper(I) catalysts for azide–alkyne [3+2] cycloadditions

• Published in: Catalysis communications 2016, Vol.73, p.103-108
• Main Authors: Gao, Xiao-Fei, Sun, Wen-Mei, Li, Xiao-Miao, Liu, Xiao-Jun, Wang, Long-Sheng, Liu, Zheng, Guo, Jun
• Format: Article
• Language: English
• Subjects: Click chemistry; Copper; Solvent-free reaction; W(Mo)/S/Cu clusters
• ISSN: 1566-7367; 1873-3905
• DOI: 10.1016/j.catcom.2015.10.019

We investigated heterothiometallic W(Mo)/S/Cu clusters [NH4]2[MS4CunXn] (M=W, Mo; X=Br, I; n=2, 4, 6) as novel copper(I) catalysts for Huisgen 1,3-dipolar cycloadditions. The experiments indicate that the thiometallic ligands can stabilize copper(I) ions and improve their solubility. Interestingly, these cluster compounds have very different catalytic performances in copper(I)-catalyzed azide–alkyne cycloadditions (CuAACs), which may correlate to their different redox potentials. Cluster [NH4]2[MS4Cu4I4] was found to be a very robust and efficient catalyst of CuAACs, and was utilized to synthesize a variety of 1,4-disubstituted 1,2,3-triazoles in excellent yields at room temperature under polar solvent or solvent-free conditions. [Display omitted] •Heterothiometallic W(Mo)/S/Cu clusters were developed as novel copper(I) catalysts.•W(Mo)/S/Cu clusters can stabilize copper(I) ions and improve their solubility.•[NH4]2[WS4Cu4I4] is a robust and efficient catalyst for CuAAC reactions.•CuAAC reactions were performed under polar solvent or solvent-free conditions.