RESUMO
Mild-mannered sulfur: A general method for the synthesis of vinyl trifluoromethyl thioethers starting from readily available di-, tri-, and tetrasubstituted vinyl iodides was developed. A wide variety of substrates were applied in the reaction with CuSCF3 to give the corresponding products in high yields, within short reaction times, with retention of the initial E/Z isomer ratio. In addition, a copper-catalyzed trifluoromethyl thioether protocol has been also developed.
RESUMO
Stronger acid, higher speed: The pKa â values of a range of binol-derived Brønsted acids of three different types were measured and found to correlate directly with the catalytic properties of the acids: higher rate constants kI were observed for more acidic Brønsted acid catalysts (see plot; binol=1,1'-bi-2-naphthol).
RESUMO
A protocol for a practical and direct addition of α- and γ-alkyl azaarenes to N-sulfonyl aldimines has been developed. Copper salts act as efficient Lewis acid catalysts for direct Mannich-type reactions providing a mild and fast access to various functionalized heterocycles.
RESUMO
The derivatives of 4-(hetero)aryl-4-oxobut-2-enoic acid are useful as building blocks in the synthesis of biologically active compounds. An efficient general protocol for the synthesis of these building blocks was developed. This method combines microwave assistance and ytterbium triflate catalyst and allows the fast preparation of the target acids starting from different (hetero)aromatic ketones and glyoxylic acid monohydrate giving pure products in 52-75% isolated yields.