carbon tetrabromide; triphenylphosphine in N,N-dimethyl-formamide 1) -25 deg C, 2) room temperature;

1: 79 percent / NaHCO3 / ethyl acetate; H2O / 1) 1h, 0 deg C 2) overnight 2: 50 percent / CBr4, triphenylphosphine / dimethylformamide / 1) -25 deg C, 2) room temperature View Scheme

1: 79 percent / NaHCO3 / ethyl acetate; H2O / 1) 1h, 0 deg C 2) overnight 2: 50 percent / CBr4, triphenylphosphine / dimethylformamide / 1) -25 deg C, 2) room temperature View Scheme