Ethyl 6-bromoindole-2-carboxylate

White solid

In a 250 mL flask, the above Ethyl-3-(4-bromo-2-nitrophenyl)-2-oxopropanoate (2.57 g, 8.15 mmol) was added thereto, Acetic acid (15 mL) and ethanol (15 mL) were added and dissolved, Iron powder (4.1 g, 73.4 mmol) was added, And the mixture was refluxed for 4 hours.After completion of the reaction, The temperature was lowered to 5 , After filtering the mixed solution using celite, And concentrated under reduced pressure.After adjusting to pH 5 with 2N HCl and extraction with ethyl acetate, The water was removed with magnesium sulfate and concentrated.next, Recrystallization from dichloromethane afforded ethyl-6-Bromo-1H-indole-2-carboxylate (1.5 g, 5.59 mmol, 68.6percent).To a suspension of 6-bromo-1H-indole-2-carboxylic acid (5.0 g, 20.8 mmol) in MeOH (100 mL) was added SOCl2 (2.26 mL, 31 mmol) very slowly. The mixture was heated under reflux until TLC analysis showed no starting material was left. Solvent was removed under reduced pressure and the crude product was collected as a brown powder (5.52 g, 99percent yield) after drying. It was used for next step reaction without purification. MS: Calcd for C11H11BrNO2 265.99 and 267.99 [M-H-], found 265.95 and 267.95 [M-H-].To a solution of Ethyl 6-bromoindole-2-carboxylate Iron powder (5.34 g, 95 mmol) was added in 1 portion to a stirred solution of ethyl 4-bromo-2-nitrophenyl acetate, potassium salt (10 g, ~ 32 mmol) in acetic acid (100 mL) at room temperature under Ar. The reaction was heated to 90 C and stirred for 45 min. After allowing to cool to room temperature the mixture was poured into saturated sodium hydrogen carbonate solution (~200 mL) and filtered through celite washing with ethyl acetate (300 mL). The filtrate was extracted with ethyl acetate (2 x 200 mL) and the combined organic extracts were dried (sodium sulfate), filtered and concentrated in vacuo to leave a crude solid. The solid was purified by flash column chromatography [SiO2; Ethyl acetate-heptane (5:1) ' Ethyl acetate)] to give the product as a yellow solid (4.6 g, 54%). IR numax (Nujol)/cm-1 3318, 2925, 2855, 1880, 1694, 1618, 1569, 1523, 1486, 1462, 1423, 1375, 1349, 1317, 1239, 1221, 1205, 1120, 1105, 1047, 1023, 975, 942, 911, 868, 852, 822, 792, 766, 735, 658, 590, 583 and 548; NMR deltaH (400 MHz; CDCl3) 9.0 (1H, br. s), 7.59 (1H, s), 7.53 (1H, d, J 8.5 Hz), 7.24 (1H, dd, J 8.5, 1.6 Hz), 7.18 (1H, d, J 1.6 Hz), 4.39 (2H, q, J 7 Hz), 1.40 (3H, t, J 7 Hz).Example 195 Synthesis of ethyl 6-cyclopropyl-1H-indole-2-carboxylate. The mixture of Example 274 Synthesis of ethyl 6-cyclopropyl-1H-indole-2-carboxylate. A mixture of

Molecular Weight:268.11
XLogP3:3.9
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:3
Exact Mass:266.98949
Monoisotopic Mass:266.98949
Topological Polar Surface Area:42.1
Heavy Atom Count:15
Complexity:247
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes