Mechanistic Insights into the Rhenium-Catalyzed Alcohol-To-Olefin Dehydration Reaction

Rhenium‐based complexes are powerful catalysts for the dehydration of various alcohols to the corresponding olefins. Here, we report on both experimental and theoretical (DFT) studies into the mechanism of the rhenium‐catalyzed dehydration of alcohols to olefins in general, and the methyltrioxorhenium‐catalyzed dehydration of 1‐phenylethanol to styrene in particular. The experimental and theoretical studies are in good agreement, both showing the involvement of several proton transfers, and of a carbenium ion intermediate in the catalytic cycle. Ionic or concerted? Rhenium‐based complexes are powerful catalysts for the dehydration of various alcohols to the corresponding olefins. Experimental and DFT studies into the mechanism of the rhenium‐catalyzed dehydration of alcohols to olefins are reported. The experimental and theoretical studies are in good agreement, both showing the involvement of a carbenium ion intermediate in the catalytic cycle (see figure).