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The subject of this investigation is a new method for the construction of sulfonylated heterocycles which overcomes the limitations of classical approaches using a cheap feedstock sulfonylating agent, especially under photocatalyst- and metal-free conditions. [ABSTRACT FROM AUTHOR]

The regioselective reductive hydration of terminal alkynes using two complementary dual catalytic systems is described. Branched or linear alcohols are obtained in 75–96% yield with ≥25:1 regioselectivity from the same starting materials. The method is compatible with terminal, di-, and trisubstituted alkenes. This reductive hydration constitutes a strategic surrogate to alkene oxyfunctionalization and may be of utility in multistep settings. [ABSTRACT FROM AUTHOR]

Alkenes and alcohols are among the most abundant and commonly used organic feedstock in industrial processes. We report a selective catalytic alkylation reaction of alkenes with alcohols that forms a carbon-carbon bond between vinyl carbon-hydrogen (C-H) and carbon-hydroxy centers with the concomitant loss of water. The cationic ruthenium complex [(C6H6)(PCy3)(C0)RuH]+BF4- (Cy, cyclohexyl) catalyzes the alkylation in solution within 2 to 8 hours at temperatures ranging from 75° to 110°C and tolerates a broad range of substrate functionality, including amines and carbonyls. Preliminary mechanistic studies are inconsistent with Friedel-Crafts-type electrophilic activation of the alcohols, suggesting instead a vinyl C-H activation pathway with opposite electronic polarization. [ABSTRACT FROM AUTHOR]

A simple and straight-forward method has been developed for direct carboxylation of terminal alkynes using CO2as the C1 carbon feedstock. The direct C–H bond functionalization is achieved with Cs2CO3as the base and in the absence of transition metal catalyst. Various propiolic acids were synthesized in good to excellent yields with a wide substrate scope and a good functional groups tolerance. This is a more atom- and step-economic protocol with great potential in practical application. [ABSTRACT FROM AUTHOR]