Bioinspired W-OH Complexes for Hydration of Acetylene

Tungsten is the heaviest metal found in living organisms, and it plays a unique and important role in certain enzymes. One such enzyme, acetylene hydratase (AH), is used by specific bacteria to support the reaction of water and acetylene (C2H2)a simple welding gasinto acetaldehyde. Further metabolic processes convert acetaldehyde to ATP, the essential energy currency of life. It is very uncommon for an alkyne to serve as a primary energy source in biology. In AH, tungsten is located at its active site, surrounded by special sulfur-rich molecules called metallopterin-cofactors and two important amino acid residues: aspartate and cysteine. The ability of acetylene hydratase to efficiently carry out the reaction between acetylene and water is remarkable, yet we still do not fully understand how it works. Unlike industrial processes, which usually require high temperatures and harmful catalysts to activate acetylene, acetylene hydratase operates at normal temperatures and pressures. It transforms acetylene into acetaldehyde (CH3CHO) without creating any toxic byproducts. Our research aims to uncover the details of how this enzyme functions, which could lead to the development of better and more environmentally friendly catalysts for similar reactions in industry. We believe that the specific amino acids surrounding the tungsten center in acetylene hydratase create an ideal environment for this reaction to occur. By studying the interactions between these amino acids, acetylene, and tungsten, we hope to replicate the enzymes function using synthetic models. To achieve this, we are designing and developing biomimetic tungsten complexes that mimic the enzymes active site. These synthetic complexes will be tested as catalysts for acetylene hydration, and detailed studies will be conducted to understand how they work. Furthermore, we are focusing on achieving water-solubility with the tungsten compounds, following green chemistry trends, and avoiding organic solvents that are toxic to the environment. By exploring these model complexes, we hope to gain insights into the enzyme`s mechanism and contribute to creating new, sustainable catalysts for similar chemical reactions in the future.