GENERAL STEPS: A mixture of 1,2,4-butanetriol (15 g, 141 mmol), acetone (100 mL, 1362 mmol), and p-toluenesulfonic acid monohydrate (700 mg, 3.68 mmol) was stirred for 16 hours at room temperature. Upon completion of the reaction, triethylamine (2 mL, 14.3 mmol) was added to the reaction mixture to neutralize the acidic catalyst and the mixture was subsequently concentrated. The resulting residue was purified by silica gel column chromatography (silica gel, eluting solvent: heptane/ethyl acetate = 1/0 → 1/1-1/3 gradient) to afford 4-(2-hydroxyethyl)-2,2-dimethyl-1,3-dioxolane (16.55 g, yield: 80.3%) as a colorless oil. 1H-NMR (400 MHz, CDCl3) δ ppm: 1.37 (3H, s), 1.43 (3H, s), 1.79-1.86 (2H, m), 2.18-2.24 (1H, br), 3.60 (1H, dd, J = 7.8 Hz), 3.76-3.86 (2H, m), 4.10 (1H, dd, J = 6.8 Hz), 4.23-4.32 (1H, m).
