Probing Solvent Effects on Reactivity: Neutron Scattering Study of 2-Butanone in Water and tert-Butanol

Solvent effects play a pivotal role in determining the rate and selectivity of catalytic reactions, yet the molecular-level origins of these effects often remain elusive. A striking example is the hydrogenation of 2-butanone (methyl ethyl ketone), which proceeds efficiently in water but is hindered or significantly slower in tert-butanol. It is suggested that tert-butanol forms a sterically congested solvation shell around the 2-butanone molecule, limiting access to the reactive carbonyl group and reducing catalytic activity. In this study, we aim to investigate the structural interactions between 2-butanone and two contrasting solvents—water and tert-butanol—using total neutron scattering across a wide Q-range (0.02 to 50 Å⁻¹). This approach will provide insight into solvation structure, hydrogen bonding, and spatial organisation at both long and short length scales. By resolving these molecular interactions, we hope to better understand how solvent environment influences catalytic performance, paving the way for more rational solvent selection in heterogeneous catalysis.