The path towards type V deep eutectic solvents: inductive effects and steric hindrance in the system tert-butanol plus perfluoro tert-butanol

The solid-liquid phase behaviour of two tertiary alcohols, perfluoro-tert-butanol and tert-butanol, was studied here using experimental (ITC, DSC and density measurements) and theoretical (MD simulations) approaches. The phase diagram of the binary mixture reveals highly negative deviations from ideality at low concentrations, as well as the formation of co-crystals and is characterized by two eutectic points, a congruent melting point and a peritectic reaction corresponding to TBH : TBF stoichiometries of 2 : 1 and 1 : 1 respectively. Excess molar enthalpies and volumes were calculated, showing negative and positive deviations from ideality, respectively. The effect of acidity, stereochemical hindrance and phobic effects and how they affect intermolecular interactions in these binary mixtures is discussed, with the aim of designing and fine-tuning type V deep eutectic solvents. The results showed that the fluorination of tertiary alcohols can be used for the tuning of the mixing properties and solid-liquid phase diagrams.

Automated summary

The solid-liquid phase behavior of perfluoro-tert-butanol and tert-butanol was investigated using experimental and theoretical methods. The study revealed the formation of co-crystals and identified two eutectic points in the binary mixture. The results showed that the fluorination of tertiary alcohols can be used to tune the mixing properties and solid-liquid phase diagrams.