To develop type V hydrophobic thymol-based Deep Eutectic Solvents (DESs) with low viscosity for liquid–liquid extraction, this work briefly reviews the thymol-based DESs reported in the literature, along with their various applications, and investigates the potential for DES formation between thymol and new materials. For this purpose, 39 combinations of thymol with different amino acids (5), acids (10), carbohydrates (13), amides (2), alkylammonium halides (4), and other compounds (5) were screened, resulting in the preparation of two new thymol-acetamide and thymol-acetanilide-based DESs. To identify the optimal molar ratios for DES formation, various combinations of thymol with acetamide and acetanilide were prepared, and their abilities to form stable liquids at room temperature, along with their thermal properties, were evaluated. Based on the solid–liquid equilibria (SLE) phase diagrams, it was found that stable liquids at ambient temperature were formed within the composition ranges of xACM = 0.29–0.40
