Molecular dynamics and experimental study of hydrogen-bonding and physicochemical properties in 2-Formyl-5-methylfuran and branched alcohols

2-Formyl-5-methylfuran (2F5M) exhibits strong intermolecular interactions that influence its physicochemical behavior in solution. In this study, molecular dynamics (MD) simulations combined with experimental measurements are employed to investigate the mixing characteristics, hydrogen-bonding patterns, and thermophysical properties of binary mixtures of 2F5M with 2-alkanols (C3–C6). The simulations, using optimized force fields, reveal pronounced non-ideal mixing dominated by hydrogen bonding between the aldehyde group of 2F5M and the hydroxyl groups of alcohols. Short-chain alcohols promote compact, hydrogen-bonded networks, while longer-chain analogues introduce steric effects that disrupt local packing. Experimental density and viscosity data validate the computational predictions, demonstrating a clear correlation between molecular-level interactions and bulk properties. These findings provide molecular insight into the role of aldehyde–alcohol association in determining liquid structure and transport behavior, and establish a computational–experimental framework for predicting the physicochemical properties of biomass-derived mixtures relevant to interfacial and solution science.