Gold Trifluoromethyl Complexes as Efficient Regioselective Catalysts in Alkyne Hydration
David Ruiz-Almoguera1, David Ventura-Espinosa1, Alberto Pérez-Bitrián2,3
1Institute of Advanced Materials (INAM), Universitat Jaume I, Avda. Sos Baynat s/n, 12006, Castellón, Spain.
Abstract:
Gold(III) complexes containing trifluoromethyl ligands are efficient catalysts in the hydration of alkynes, operating at low catalyst loadings, without additives, using environmentally friendly solvents and at mild conditions (60 °C). Hydration of terminal and internal alkynes provides the corresponding ketones in quantitative yields without special precautions as dry solvents or inert atmospheres. Remarkably, hydration of asymmetric internal alkynes proceeds with moderate to notable regioselectivities, providing mixtures of the two possible isomers with ratios up to 90 : 10.
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