Facile access to trifluoromethyl propargyl alcohol by metal-free transfer hydrogenation and cyanation of alkynyl ketones.

We report an efficient synthetic route to the metal-free hydroboration and cyanosilylation of a wide range of alkynyl trifluoromethyl ketones using pinacolborane (4,4,5,5-tetramethyl-1,3,2-dioxaborolane) and trimethylsilyl cyanide under mild reaction conditions at ambient temperature. These highly effective hydroboration and cyanosilylation reactions lead to the corresponding alkynyl trifluoromethyl propargyl alcohols after hydrolysis. In addition, trifluoromethyl (CF) group-based pharmaceutically active enflicoxib analogs were synthesized from propargyl alcohol.

Hydroboration and reductive amination of ketones and aldehydes with HBpin by a bench stable Pd(II)-catalyst.

A palladium(II) complex [(κ-{1,2-CH(NCH-CHO)}Pd] (1) supported by a dianionic salen ligand [1,2-CH(NCH-CHO)] (L) was synthesised and used as a molecular pre-catalyst in the hydroboration of aldehydes and ketones. The molecular structure of Pd(II) complex 1 was established by single-crystal X-ray diffraction analysis. Complex 1 was tested as a competent pre-catalyst in the hydroboration of aldehydes and ketones with pinacolborane (HBpin) to produce corresponding boronate esters in excellent yields at ambient temperature under solvent-free conditions.