To a -78° C. solution of the ester from Step 1 (35 mg, 0.08 mmol) in 3 mL THF was added LDA (1.5M in cyclohexane, 0.1 mL, 0.15 mmol), and the solution was stirred for 30 min. A solution of iodomethane (0.1 mL, 1.6 mmol) in 1 mL HMPA was then added by syringe. The solution was stirred 15 min at -78° C., then warmed to 0° C. and quenched with saturated NH4Cl. The mixture was partitioned between ether and water and the organic layer was washed with water and brine and dried over MgSO4. The residue was purified by flash chromatography (15% ethyl acetate/hexanes) to provide 24 mg of the title compound.
