1: With sodium hydride in ethylene glycol dimethyl ether T=20°C; 1 h; 2: With bromine in ethylene glycol dimethyl ether T=0 - 20°C; 2.25 h;

1: 85 percent / NaOH; Br2 / H2O 2: 70 percent / SnCl2*2H2O / aq. ethanol / 0.67 h / -25 °C View Scheme

1: methyl bis(2,2,2-trifluoroethoxy)bromophosphonoacetate With 18-crown-6 ether; potassium tert-butylate in tetrahydrofuran; acetonitrile T=-78°C; Metallation; 0.5 h; 2: benzaldehyde in tetrahydrofuran T=-78°C; Horner-Wadsworth-Emmons reaction; 0.333333 h; Further stages.;