4-Bromo-2-nitrotoluene → 4-Bromo-7-methyl-1H-indole

Beteiligte Stoffe

Reaktionsschritte

To a solution of 4-bromo-1-methyl-2-nitrobenzene (10 g) in THF (130 mL) was slowly added vinylmagnesium bromide (1 M in THF, 162 mL) at −40° C. under nitrogen atmosphere. The reaction mixture was stirred for 1.5 h and then quenched with sat'd. aq. NH4Cl (50 mL). The mixture was partitioned between EtOAc (500 mL) and water (150 mL). The organic layer was separated, washed with brine, dried (MgSO4), filtered, and evaporated in vacuo. The residue was purified by SiO2 chromatography eluting with 2.5% EtOAc/petroleum ether to afford 1.54 g (16%) of 4-bromo-7-methyl-1H-indole (306) as brown solid: MS (ESI) m/z=209.9 [M+1]+.

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