[C:1]([O:5][C:6](=[O:19])[NH:7][C:8]1[S:9][C:10]([F:18])=[C:11]([CH2:13]N(OC)C)[N:12]=1)([CH3:4])([CH3:3])[CH3:2].Cl[O-].[Na+].S1C=C(C=[O:29])N=C1.[BH4-].[Na+].Cl>C1COCC1.O>[C:1]([O:5][C:6](=[O:19])[NH:7][C:8]1[S:9][C:10]([F:18])=[C:11]([CH2:13][OH:29])[N:12]=1)([CH3:4])([CH3:3])[CH3:2]A solution of Intermediate 104: {5-Fluoro-4-[(methoxy-methyl-amino)-methyl]-thiazol-2-yl}-carbamic acid tert-butyl ester (7.5 g, 25.7 mmol) in THF (45 mL) and water (4.5 mL) was rapidly stirred and treated slowly dropwise with 6.15% sodium hypochlorite solution in water (Clorox™, 67 mL, 55 mmol). The resulting thiazole-4-carboxaldehyde was reduced in situ with sodium borohydride (0.5 g). The reaction was acidified with 2 N HCl (10 mL) and extracted with diethyl ether (2×50 mL). The extracts were dried with sodium sulfate and evaporated to leave an orange resin which purified by silica gel chromatography (80% EtOAc/hexane) to afford (4-hydroxymethyl-5-fluoro-thiazol-2-yl)-carbamic acid tert-butyl ester as a yellow foam (2.9 g, 45% yield).
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