ethyl 6-oxospiro[2.5]octane-2-carboxylate

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of ethyl (1S)-6-oxospiro[2.5]octane-1-carboxylate (1.9 g, 7.91 mmol) in acetone (20 mL) and water (5 mL) was added PPTS (0.1 g, 0.398 mmol). The reaction mixture was heated at 60° C. for 5 h, and then stirred at rt for 45 h. The reaction mixture was diluted with EtOAc, washed with water, brine, dried (MgSO4) and concentrated to afford ethyl 6-oxospiro[2.5]octane-1-carboxylate as an oil (1.32 g). 1H NMR (400 MHz, CDCl3) δ ppm 4.13-4.21 (2H, m), 2.35-2.51 (3H, m), 2.19-2.30 (1H, m), 2.00-2.09 (3H, m), 1.86 (1H, ddd, J=13.68, 8.16, 5.27 Hz), 1.64-1.77 (2H, m), 1.23-1.35 (3H, m), 1.08 (1H, dd, J=8.16, 4.64 Hz). washed with water, brine dried (MgSO4) concentrated

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of ethyl (1S)-6-oxospiro[2.5]octane-1-carboxylate (1.9 g, 7.91 mmol) in acetone (20 mL) and water (5 mL) was added PPTS (0.1 g, 0.398 mmol). The reaction mixture was heated at 60° C. for 5 h, and then stirred at rt for 45 h. The reaction mixture was diluted with EtOAc, washed with water, brine, dried (MgSO4) and concentrated to afford ethyl 6-oxospiro[2.5]octane-1-carboxylate as an oil (1.32 g). 1H NMR (400 MHz, CDCl3) δ ppm 4.13-4.21 (2H, m), 2.35-2.51 (3H, m), 2.19-2.30 (1H, m), 2.00-2.09 (3H, m), 1.86 (1H, ddd, J=13.68, 8.16, 5.27 Hz), 1.64-1.77 (2H, m), 1.23-1.35 (3H, m), 1.08 (1H, dd, J=8.16, 4.64 Hz). washed with water, brine dried (MgSO4) concentrated