The general procedure for the synthesis of (benzyloxycarbonylmethylene)triphenylphosphonium bromide from benzyloxycarbonylmethylene)triphenylphosphonium bromide was as follows: (2-(benzyloxy)-2-oxoethyl)triphenylphosphonium bromide (2.00 g, 4.07 mmol) and NaOH (0.081 g, 2.035 mmol) were dissolved in CH2Cl2 (20 mL), and the reaction was stirred for 1 hr at 25 °C . After completion of the reaction, the reaction mixture was diluted with CH2Cl2 (50 mL) and washed with deionized water (30 mL). The organic layer was separated and concentrated to afford benzyl 2-(triphenylphosphoranylidene)acetate (1.5 g, 3.25 mmol, 80% yield). The product was characterized by 1H NMR (400 MHz, CDCl3): δ 7.60-7.65 (m, 6H), 7.51-7.54 (m, 4H), 7.42-7.46 (m, 6H), 7.20 (s, 4H), 5.00 (s, 2H), 2.96 (s, 1H); LC-MS(ESI) m/z 411.1 (M + H) +.
