Hydrochloric Acid → 4-(4-Bromo-2-chloro-phenyl)-1-methyl-3-(2-pyridyl)-4,6,7,8-tetrahydropyrazolo[3,4-e][1,4]thiazepine

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Reaction Conditions

Reaction Steps

To a solution of 4-(4-bromo-2-chloro-phenyl)-1-methyl-3-(2-pyridyl)-4,8-dihydropyrazolo[3,4-e][1,4]thiazepin-7-one (5.83 g, 13.0 mmol) in THF (50 mL) was added a solution of borane THF complex (40 mL, 1M in THF, 40 mmol, Acros) at rt. Subsequently, the mixture was heated under reflux for about 2 h. After cooling to about 4° C., HCl (5 M aq, 40 mL) was added dropwise and the mixture was stirred for about 18 h at rt, then NaOH (2 M aq, 110 mL) and ethyl acetate (200 mL) were added. The layers were separated and the aqueous layer was extracted with ethyl acetate (50 mL). The combined organic layers were washed with water (2×50 mL), dried (MgSO4), filtered and concentrated in vacuo. The residue was purified by column chromatography (SiO2, ethyl acetate) to give 4-(4-bromo-2-chloro-phenyl)-1-methyl-3-(2-pyridyl)-4,6,7,8-tetrahydropyrazolo[3,4-e][1,4]thiazepine (4.86 g, 11.1 mmol, 86%). LC-MS (Table 1, Method a) Rt=4.54 min, m/z 435, 437 (M+H)+

Provenance & Evidence