[CH3:1][O:2][CH2:3][C:4]1[S:5][CH:6]=[C:7]([C:9](OCC)=[O:10])[N:8]=1.CC(C[AlH]CC(C)C)C.C(O)(=O)C.C(C(C(C([O-])=O)O)O)([O-])=O.[K+].[Na+]>ClCCl>[CH3:1][O:2][CH2:3][C:4]1[S:5][CH:6]=[C:7]([CH:9]=[O:10])[N:8]=1
A solution containing the product from Example 6C (7.4 g, 36.8 mmol) in dichloromethane (40 mL) was treated with DIBAL (73.6 mL, 1 M in dichloromethane) dropwise at −78° C. over 2 hours, stirred at −78° C. for 2 hours, treated with acetic acid (10 mL) at −78° C. and warmed to 25° C. A 10% solution of aqueous sodium potassium tartrate was added and the mixture was stirred vigorously for 1 hour. The reaction mixture was partitioned between chloroform and water. The organic phase was washed with brine, dried over MgSO4, filtered and concentrated. The residue was chromatographed on silica gel eluting with 0-100% ethyl acetate/dichloromethane to give the title compound (5.78 g, 71% yield).
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