Synthesis
General procedure for the synthesis of 3-bromo-1-(triisopropylmethylsilyl)pyrrole from 1-(triisopropylmethylsilyl)pyrrole: at -78 °C, N-bromosuccinimide (NBS, 3.25 g, 18.3 mmol) was slowly added to a 1-(triisopropylmethylsilyl)pyrrole (3.72 g, 16.6 mmol) solution of tetrahydrofuran (THF, 17 mL ) solution was maintained at temperature and stirred continuously for 5 hours. Upon completion of the reaction, hexane (15 mL) and pyridine (0.5 mL) were added to the mixture and stirring was continued for 5 minutes. Subsequently, the solvent was removed by distillation under reduced pressure to give the crude product. The crude product was purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=30:1) to finally obtain 3-bromo-1-(triisopropylmethylsilyl)pyrrole (4.67 g, 93% yield) as a colorless oil.
References
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