(3-Benzyloxy-4-nitrophenyl)-acetic acid ethyl ester (Step C) (1.90 g, 6.03 mmol) and 2-benzyloxy-6-fluorobenzonitrile (Step D) (2.74 g, 12.1 mmol) are dissolved in DMF (18 mL) and added dropwise to a suspension of Cs2CO3 (5.89 g, 18.1 mmol) in DMF (18 mL). The mixture is heated to 80° C. for 1.5 h, then stirred at 60° C. for 16 h. The mixture is diluted with EtOAc (350 mL) and extracted with 1N HCl (2×75 mL), followed by brine (75 mL). The organic phase is dried over Na2SO4 and concentrated. The residue is taken up in THF (18 mL), MeOH (18 mL) and 1N NaOH (36 mL). Decarboxylation is complete after 2 h, the reaction mixture is poured into ice water (100 mL) and acidified to pH ˜2 with 6N HCl. The mixture is extracted with EtOAc (2×200 mL) and the organic phase is washed with brine (75 mL), dried over Na2SO4 and concentrated to afford a brown oil. Purification by flash column (10-75% EtOAc/hexanes) affords 2-benzyloxy-6-(3-benzyloxy-4-nitrobenzyl)-benzonitrile as an off-white solid: MS (M+H)+=451.
