Ruthenium-Catalyzed Deoxygenative Hydroboration of Carboxylic Acids

An efficient deoxygenative hydroboration of carboxylic acids to alkyl boronate esters under mild reaction condition is reported. Both aromatic and aliphatic carboxylic acids exhibited excellent reactivities with minimal catalyst load of 0.1 mol % and reactions occurred under neat conditions. This catalytic transformation selectively provides alkyl boronate esters, which can be conveniently hydrolyzed to obtain the corresponding alcohols. Remarkably, this reduction reaction proceeds with the liberation of molecular hydrogen.