Chlorotrimethylsilane → 2-(4-Bromo-2-chlorophenyl)ethanamine

Participants

Reaction Steps

To a stirred suspension of LiBH4 (2.0 M, 73 mL, 145 mmol) in THF (60 mL) at room temperature was added chlorotrimethylsilane (32 g, 290 mmol), dropwise over 10 min. After stirring at room temperature for 20 min, nitrogen gas was bubbled through the mixture for 5 min to remove the remaining trimethylsilane that had formed. A solution of 4-bromo-2-chloro-1-(2-nitrovinyl)benzene (9.5 g, 36.2 mmol) in THF (60 mL) was added dropwise over 10 min with stirring at room temperature. The resulting mixture was heated at reflux for 1 h. The reaction mixture was cooled in an ice bath and carefully quenched with MeOH (100 mL). The solvent was evaporated and the residue was partitioned between 20% KOH (120 mL) and CH2Cl2 (60 mL). The organic layer was dried, concentrated, purified by column chromatography (silica, ethyl acetate/hexanes gradient) to obtain the desired product (8.5 g, 95%) as a light yellow oil: ESI MS m/z 234 [C8H9BrClN+H]+.

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