5-Bromo-2,3-dimethylindole

A 500 ml_ three neck round bottomed flask equipped with a stir bar, thermocouple, heat mantle, and water condenser with nitrogen inlet was charged with 3-bromophenylhydrazine hydrochloride (19.84 g, 88.77 mmol) and isopropanol (240 ml_). 2-Butanone (8.0 ml_, 89.32 mmol) was added and the reaction was heated to 80 °C. After 4 days the reaction was allowed to cool to room temperature. The solvent was removed by rotary evaporation and the red residue dissolved in ethyl acetate (200 ml_). The organic layer was washed with 1 N hydrochloric acid (100 ml_) and saturated aqueous sodium bicarbonate (100 ml_). The organic layer was dried over magnesium sulfate, filtered, and concentrated by rotary evaporation to give 5- bromo-2, 3-dimethyl-1 H-indole as a red solid (1 5.94 g, 71 .1 mmol, 80percent). Following a published procedure (Gundersen, E. G. U.S. Patent App. Publ. US 2005/070592) 2-Butanone (0.11 mL, 1.278 mmol) was added to a solution of 4-bromophenylhydrazine hydrochloride (0.300 g, 1.342 mmol in EtOH (3.8 mL). A 500 mL three neck round bottomed flask, equipped with a stir bar, thermocouple, heat mantle, and water condenser, and with a nitrogen inlet, was charged with 3-bromophenylhydrazine hydrochloride (17) (19.84 g, 88.77 mmol) and isopropanol (240 mL) . 2-Butanone (18) (8.0 mL, 89.32 mmol) was added and the reaction was heated to 80. After 4 days, the reaction was allowed to cool to room temperature. The solvent was removed by rotary evaporation and the red residue dissolved in ethyl acetate (200 mL) . The organic layer was washed with 1N HCl (100 mL) and saturated aqueous sodium bicarbonate (100 mL) . The organic layer was dried over magnesium sulfate, filtered, and concentrated by rotary evaporation to give indole compound (19) as red solids (15.94 g, 71.1 mmol, 80) .Preparation of 5-bromo-2, 3~dimethylindole A mixture of 4-bromophenylhydrazine (5.0 g, 22.3 mmoi) and methyl ethyl ketone (1.6 g, 22.3 mmoi) was heated in ethanof (60 mL) at refiux overnight. The solvent was removed under vacuum and the residue recrystaliized from ethanol/water, to give the target compound (3.6 g, 73percent). NMR (400 MHz, d

Molecular Weight:224.10
XLogP3:3.5
Hydrogen Bond Donor Count:1
Exact Mass:222.99966
Monoisotopic Mass:222.99966
Topological Polar Surface Area:15.8
Heavy Atom Count:12
Complexity:171
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes