Water Catalysis in the Morita-Baylis-Hillman Reaction: A Mechanistic Perspective

A study was conducted to investigate the effect of water molecules in the Morita-Baylis-Hillman (MBH) reaction. The MBH reaction is a tertiary amine catalyzed reaction of an activated olefin and an electrophile that produce a dense functionalized product. The study also determined the gas phase with and without explicit water molecules and condensed phase with water-bound molecules. Water molecules were placed around the substrate to determine the minimal number of bound solvent molecules. It was observed during the study that the explicit water molecules in transition-state models can reduce the activation barrier between acrolein and formaldehyde by using tremethylamine catalysis. The study concluded that the presence of loosely bound co-solvents can produce many near-degenerate transition states during the MBH reaction.