Regioselective Gold-Catalyzed Hydration of CF3- and SF5-alkynes.

The regioselective gold-catalyzed hydration of CF3- and SF5-alkynes is described. The corresponding trifluoromethylated and pentasulfanylated ketones are obtained in up to 91% yield as single regioisomers showcasing the use of CF3 and SF5 as highly efficient directing groups in this reaction. Notably, this transformation represents the first use of CF3- and SF5-alkynes in gold catalysis.

Use of XtalFluor-E as an Alternative to POCl3 in the Vilsmeier-Haack Formylation of C-2-Glycals.

We report the use of XtalFluor-E ([Et2NSF2]BF4) as an alternative to POCl3 in the Vilsmeier-Haack formylation reaction of C-2-glycals. Employing a XtalFluor-E/DMF combination allowed the desired C-2-formyl glycals to be isolated in 11-90% yield. This method was extended to the synthesis of a C-2 -formylated disaccharide glycal.