Di-tert-butyl [4-(1,3-dioxolan-2-yl)-3-fluorophenyl]malonate (2.45 g, 6.41 mmol), iodomethane (0.80 mL, 12.85 mmol) and potassium carbonate (1.78 g, 12.9 mmol) were suspended in DMF (10 mL) and heated at 70° C. for 3 hours in a sealed tube. A further portion of iodomethane was added (0.60 mL, 9.64 mmol) and heating continued at 75° C. for 3 hours. Room temperature was attained, H2O (150 mL) was added and the products extracted into Et2O (2×100 mL). The combined organic extracts were washed with brine, dried over MgSO4 and concentrated in vacuo. Purification of the residue by MPLC gave 0.91 g of clean product (orange oil, 36%). 1H NMR (CDCl3) δ 7.47 (t, J=8.1 Hz, 1H), 7.19 (dd, J=8.1, 1.8 Hz, 1H), 7.17 (dd, J=12.0, 1.8 Hz, 1H), 6.07 (s, 1H), 4.13 (m, 2H), 4.03 (m, 2H), 1.74 (s, 3H), 1.45 (s, 18H).
