Ethylene Glycol → Ethyl 1,4-dioxaspiro(4.5)decane-8-carboxylate

Participants

Reaction Steps

A mixture of 4-ethoxycarbonyl-cyclohexanone (11.0 g, 64.6 mmol), 1,2-ethanediol (6.02 g, 96.9 mmol), and p-TsOH.H2O (620 mg, 3.2 mmol) in toluene (60 mL) was refluxed using a Dean-Stark to collect water overnight. The mixture was cooled to rt, then quenched with sat. aq. NaHCO3 (30 mL) and diluted with EtOAc (100 mL). The organic layer was washed with brine (30 mL), and dried over anhydrous sodium sulfate. The solvents were evaporated under reduced pressure to give the title compound as a light-yellow oil. 13.8 g, 100% yield. The material was used in next step without further purification. 1H NMR (CDCl3): 1.25 (t, J=7.1 Hz, 3H), 1.52-1.60 (m, 2H), 1.76-1.83 (m, 4H), 1.92-1.97 (m, 2H), 2.34 (m, 1H), 3.95 (s, 4H), 4.13 (q, J=7.1 Hz, 2H).

Provenance & Evidence