N[C:2]1[CH:3]=[CH:4][C:5]([OH:11])=[C:6]([C:8](=[O:10])[CH3:9])[CH:7]=1.N([O-])=O.[Na+].[I-:16].[K+].C(=O)([O-])O.[Na+]>S(=O)(=O)(O)O.O.[Cu]>[I:16][C:2]1[CH:3]=[CH:4][C:5]([OH:11])=[C:6]([C:8](=[O:10])[CH3:9])[CH:7]=1To a stirring solution of 1-(5-amino-2-hydroxy-phenyl)-ethanone (6.856 g,46 mmol) in 98% sulfuric acid (24 ml) and water (19 ml) was added sodium nitrite (3.30 g, 48 mmol, 1.05 equ) in water (5.5 ml). The reaction was stirred for 35 minutes, then sulfuric acid (4 ml), copper powder (0.17 g, 0.3 mmol, 0.06 equ) and potassium iodide (8.80 g, 53 mmol, 1.16 equ) in water (5.5 ml) added. The mixture was then heated slowly to 65° C. and maintained at 65° C. for 2 hours. The reaction was then cooled, water (25 ml) and sodium hydrogen carbonate added. More water was added, then extracted into a mixture of ethyl acetate and dichloromethane, then ethyl acetate (2×). The combined organic layers were washed with brine then concentrated in vacuo. This mixture was then taken up in ethyl acetate and 2 M HCl, filtered and the organic layer dried (MgSO4) and concentrated in vacuo to give 1-(5-iodo-2-hydroxy-phenyl)-ethanone 52 (1.339 g, 39%) as a purple oil. This was then used in the next reaction.
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