Au(I)-Catalyzed Regioselective Hydrogen Isotope Labeling of Indoles
Pierre Milcendeau1, Pierre Colonna2, Mohammed Ramdani1
1Université Paris-Saclay, CNRS, Institut de Chimie des Substances Naturelles, UPR 2301, 91198 Gif-sur-Yvette, France.
Abstract:
The gold(I)-catalyzed hydrogen isotope exchange reaction on indoles and related heterocycles is described under mild conditions and low catalyst loadings, using CD3OD and D2O as readily available deuterium sources. C3-unsubstituted indoles are labeled at the C3 position with exquisite regioselectivity, while C3-substituted indoles are labeled at the C2 position. The method is also applicable to the regioselective tritiation of indoles. Mechanistic studies revealed the involvement of aurated indoles as key intermediates.
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