Compound 453 (5.4 g, 9.56 mmol), iron powder (1.602 g, 28.69 mmol) and NH4Cl (0.78 g, 14.34 mmol) were placed in a mixture of H2O (24mL) and EtOH (48 mL). The reaction mixture was heated to reflux for 5 h. It was then cooled to RT, diluted with MeOH and filtered through a pad of celite. The filtrate was concentrated to dryness and the residue was dissolved in dichloromethane, washed with aqueous NaHCO3 and brine, dried over Na2SO4, and filtered. The filtrate was concentrated to dryness to give compound 454 as white solid (4.2 g, 83% yield). LCMS: 535 (M+H)+.
