[OH:1][C:2]1([C:15]2[S:16][CH:17]=[CH:18][N:19]=2)[CH2:7][CH2:6][CH:5]([C:8]([O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:9])[CH2:4][CH2:3]1.CN(C=O)C.C1C(=O)N([Br:32])C(=O)C1>O.C(OCC)(=O)C>[Br:32][C:17]1[S:16][C:15]([C:2]2([OH:1])[CH2:7][CH2:6][CH:5]([C:8]([O:10][C:11]([CH3:14])([CH3:12])[CH3:13])=[O:9])[CH2:4][CH2:3]2)=[N:19][CH:18]=1To a flask containing the product of Step 1 (925 g, 33 mmol) was added DMF (36 mL) and then n-bromosuccinimide (6.97 g, 32 mmol). The reaction was allowed to stir until complete by LCMS. The reaction was diluted with water and ethyl acetate. The organic layer was separated, dried over magnesium sulfate, filtered and concentrated. Flash chromatography was used for purification to yield tert-butyl 4-(5-bromo-1,3-thiazol-2-yl)-4-hydroxycyclohexane-carboxylate (9.24 g, 25.5 mmol, 78% yield). MS ESI: [M+H]+ m/z 364.0.
Wird geladen…