1H-Indole-7-carboxylic acid, 5-bromo-2,3-dihydro-, methyl ester

1-(1 , 1-dimethylethyl) 7-methyl 5-bromo-2, 3-dihydro-1 H-indole-1 , 7-dicarboxylate (9 g, 25 mmol) was dissolved in trifluoroacetic acid (6 ml.) and stirred at room temperature for 16 hours. Dichloromethane and sodium hydroxide solution (2 M) were added and the organic layer washed twice with sodium hydroxide solution until the aqueous layer pH > 7. The organic layer was then concentrated in vacuo to give 6.5 g (100percent) of the title compound as a brown solid.1 H NMR (400 MHz, DMSO-D6) δ ppm 2.99 (t, J=8.5 Hz, 2 H) 3.61 (t, J=8.4 Hz, 2 H) 3.78 (s, 3 H) 6.72 (s, 1 H) 7.28 (d, J=1 Hz, 1 H) 7.46 (d, J=2 Hz, 1 H); MS m/z 256/258 (1 :1 ratio) (M+1)Intermediate 7:Methyl 5-bromo-2, 3-dihydro-1 H-indole-7-carboxylate.1 -(1 , 1 -dimethylethyl) 7-methyl 5-bromo-2, 3-dihydro-1 H-indole-1 , 7-dicarboxylate (9 g, 25 mmol) was dissolved in trifluoroacetic acid (6 ml.) and stirred at room temperature for 16 hours. Dichloromethane and sodium hydroxide solution (2 M) were added and the organic layer washed twice with sodium hydroxide solution until the aqueous layer pH > 7. The A mixture of methyl 5-bromo-1, N-(t-butoxycarbonyl)indoline-7-carboxylate (19.5 g, 54.7 mmol) in TFA (15 mL) was stirred at 25 °C for 16 hours. TLC (petroleum ether: ethyl acetate=10:1, Rf = 0.35) indicated that starting material was consumed completely and a major new spot with lower polarity was detected. The reaction was diluted with DCM (100 mL) and adjusted to pH=9 with sat. NaHCO3. The organic phase was separated and concentrated under reduced pressure to give compound methyl 5-bromoindoline-7-carboxylate (13.5 g, 96percent yield) as a brown solid. 1H NMR (400 MHz DMSO) = 7.45 (s, 1H), 7.27 (s, 1H), 6.72 (s, 1H), 3.77 (s, 3H), 3.61(m, 2H), 2.99 (m, 2H). ESI-MS (m/z): 260.0 (M+H)+

Molecular Weight:256.10
XLogP3:2.5
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:2
Exact Mass:254.98949
Monoisotopic Mass:254.98949
Topological Polar Surface Area:38.3
Heavy Atom Count:14
Complexity:234
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes