Boron tribromide → HCID 22918414, compound

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Reaction Steps

To a suspension of 78 mg (0.18 mmol) of 4-anilino-5-(3,4,5-trimethoxy-anilino)-phthalimide (Example 27) in 4 ml ofdichloromethane, a solution of 314 μl (3.24 mmol) boron tribromide is added dropwise at RT. The reaction mixture is stirred for 4 hours at RT, is then cooled to 0° and quenched with 5 ml of water, and the phases are separated. The water phase is extracted three times with ethyl acetate. The organic phases are combined and washed twice with water, dried over magnesium surf ate and concentrated by evaporation. Excluding light, the evaporation residue is chromatographed with ethylacetate/dichloromethane 4:1 on a silica gel column (precoated with 0.4 g of sodium ascorbate per g silica gel) that is cooled with ice-water (double jacket), the product fractions are combined and concentrated by evaporation yielding the title compound in the form of dark red crystals, m.p. 152° C. (decomp.), FAB-MS: 378 [M+ +H].

Provenance & Evidence