Ruthenium-catalyzed formation of pyrazoles or 3-hydroxynitriles from propargyl alcohols and hydrazines

Functionalized pyrazoles are generated from secondary propragyl alcohols and hydrazines in a rutheniumcatalyzed cascade process, consisting of redox isomerization, Michael addition, cyclocondensation and dehydrogenation steps.The same bifunctional catalyst mediates the conversion of tertiary propargyl alcohols with hydrazine to 3-hydroxynitriles via anti-Markovnikov hydroamination followed by elimination of ammonia.