To the mixture of the compound from Step B (10 gm), 5.6 gm of sodium acetate 100 mL of ethanol was added over 15 minutes 15.5 mL of cyanogen bromide 3M in dichloromethane. The reaction mixture was stirred at ambient temperature until reaction completion. When the reaction was judged complete, it was diluted with 200 mL of toluene and 200 mL of sodium hydroxide. The layers were separated and the organic layer dried with magnesium sulfate, filtered and concentrated to an oil. 7.8 gm (74% yield). The product was used in the next step without further purification. 1H NMR (400 MHz, CDCl3) 7.84 (s, 2H), 7.56 (s, 3H), 7.66 (m, 4H), 7.48 (s, 2H), 4.39 (s, 2H), 4.36 (s, 2H)
