C[O:2][C:3](=O)[C:4]1[CH:9]=[CH:8][C:7]([C:10]2[S:11][C:12]3[CH:18]=[CH:17][CH:16]=[CH:15][C:13]=3[N:14]=2)=[CH:6][CH:5]=1.CC(C[AlH]CC(C)C)C.C(C(C(C([O-])=O)O)O)([O-])=O.[K+].[Na+]>C1COCC1>[S:11]1[C:12]2[CH:18]=[CH:17][CH:16]=[CH:15][C:13]=2[N:14]=[C:10]1[C:7]1[CH:8]=[CH:9][C:4]([CH2:3][OH:2])=[CH:5][CH:6]=1To a 0° C. solution of methyl-4-(benzothiazol-2-yl)-benzoate (prepared as described by A. Brembilla, D. Roizard and P. Lochon Synth. Commun. 1990, 20, 3379) (1.08 g, 4 mmol) in THF (20 mL) was added DIBAL-H (20 mL of a 1.0M solution in THF, 20 mmol) over 10 minutes. The resulting solution was stirred at 0° C. for 2 hours, then an aqueous saturated solution of sodium potassium tartrate was added and the biphasic mixture stirred rapidly for 60 min. The phases were separated and the aqueous layer extracted with ether (3×20 mL). The combined organic fractions were dried (Na2SO4), concentrated and purified by column chromatography on silica gel (10:1 CH2Cl2/MeOH) to afford the title compound (0.69 g, 75%). 1H NMR (CD3OD) δ 4.69 (s, 2H), 7.43 (t, 1H, J=7.8 Hz), 7.53 (m, 3H), 7.99 (m, 1H), 8.06 (m, 3H).
Wird geladen…
