Dissecting Anion Effects in Gold(I)-Catalyzed Intermolecular Cycloadditions
نویسندگان
چکیده
From a series of gold complexes of the type [t-BuXPhosAu(MeCN)]X (X=anion), the best results in intermolecular gold(I)-catalyzed reactions are obtained with the complex with the bulky and soft anion BAr4F- [BAr4F-=3,5-bis(trifluoromethyl)phenylborate] improving the original protocols by 10-30% yield. A kinetic study on the [2+2] cycloaddition reaction of alkynes with alkenes is consistent with an scenario in which the rate-determining step is the ligand exchange to generate the (η2-phenylacetylene)gold(I) complex. We have studied in detail the subtle differences that can be attributed to the anion in this formation, which result in a substantial decrease in the formation of unproductive σ,π-(alkyne)digold(I) complexes by destabilizing the conjugated acid formed.
منابع مشابه
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Shanghai Key Laboratory of Green Chem Chemistry and Molecular Engineering, Ea Zhongshan Road, Shanghai 200062, C [email protected] State Key Laboratory of Organometallic C Chemistry, CAS, 345 Lingling Road, Shangh † Electronic supplementary information compounds, experimental procedures mechanisms. CCDC 1036866 and 103686 CIF or other electronic format see DOI: 10 Cite this: Chem. Sci., ...
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