Enantioconvergent Hydrobenzylation of Racemic Allylic Alcohols with Aryl Hydrazones via Bifunctional Ruthenium Catalysis.

The use of hydrazones as carbanion equivalents for carbon-carbon bond formation reactions has emerged as a versatile tool for organic synthesis. However, the enantioselective formation of carbon-carbon bonds with hydrazones has been underdeveloped. We have developed a Ru-catalyzed enantioconvergent hydrobenzylation of racemic allylic alcohols using aryl hydrazones as latent alkyl nucleophiles.

[2+2+1+1] Cycloaddition for de novo Synthesis of Densely Functionalized Phenols.

A unique benzannulation strategy for regioselective de novo synthesis of densely functionalized phenols is described. Through metal-mediated formal [2+2+1+1] cycloaddition of two different alkynes and two molecules of CO, a series of densely functionalized phenols were obtained. The benzannulation strategy allows efficient regioselective installation up to five different substituents on a phenol ring.