[CH2:1]([O:3][C:4]([CH:6]1[CH2:11][CH2:10][CH2:9][CH2:8][C:7]1=[O:12])=[O:5])[CH3:2].CCN(C(C)C)C(C)C.FC(F)(F)S(OS(C(F)(F)F)(=O)=O)(=O)=O>ClCCl>[CH2:1]([O:3][C:4]([C:6]1[CH2:11][CH2:10][CH2:9][CH2:8][C:7]=1[OH:12])=[O:5])[CH3:2]Combine 2-oxo-cyclohexanecarboxylic acid ethyl ester (10.0 g, 55.0 mmol), Hunig's base (23.0 mL, 132.0 mmol), dichloromethane (100.0 mL), and trifluoromethane sulphonic anhydride (11.1 mL, 66.0 mmol) at −78° C. and then stir at room temperarture for 18 hours under a nitrogen atmosphere. Add water, then wash with sat sodium bicarbonate solution, citric acid, then brine, and dry over sodium sulfate. Concentrate under vacuum and flash chromatograph using 10% to 40% DCM/hexanes eluent to yield the titled compound (13.6 g, 82%). TLC Rf=0.25 in 40% DCM/hexanes. 1H NMR (CDCl3): 4.26 (q, 2H, J=7.0 Hz), 2.5 (m, 2H), 2.4 (m, 2H), 1.8 (m, 2H), 1.7 (m, 2H), 1.3 (t, 3H, J=7 Hz).
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