[Br:1][C:2]1[S:6][C:5]([C:7]2([OH:17])[CH2:16][CH2:15][C:10]3(OCC[O:11]3)[CH2:9][CH2:8]2)=[N:4][CH:3]=1.Cl.[OH-].[Na+]>C1COCC1.CCOC(C)=O>[Br:1][C:2]1[S:6][C:5]([C:7]2([OH:17])[CH2:8][CH2:9][C:10](=[O:11])[CH2:15][CH2:16]2)=[N:4][CH:3]=1
The product of Step 2 (15 g, 46.8 mmol) was diluted with THF (10 mL). HCl (6 N, 78 mL) was added and stirred at 60° C. for 3 h. The reaction was cooled to RT and NaOH (6 N, 78 mL) was added. The reaction was diluted with EtOAc. The layers were separated and the aqueous layer back extracted with EtOAc (2×). The combined organic layers were dried (MgSO4) and evaporated. The residue was diluted with EtOAc to transfer and concentrated to ˜20 mL where hexanes (60 mL) was added drop wise. The slurry was cooled to room temperature, stirred for 1 h then filtered, washed with hexanes (2×15 mL) and dried to afford 4-(5-bromo-1,3-thiazol-2-yl)-4-hydroxycyclohexanone (11.25 g, 40.8 mmol, 87% yield).
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