1-Bromopropane → 6-bromo-2-propyl-2H-indazole-4-carboxylic acid methyl ester

HRID 85457Notes

Reaction equation

HRID 85457 reaction equation
[CH3:1][O:2][C:3]([C:5]1[C:6]2[CH:7]=[N:8][NH:9][C:10]=2[CH:11]=[C:12]([Br:14])[CH:13]=1)=[O:4].[CH2:15](Br)[CH2:16][CH3:17]>>[CH3:1][O:2][C:3]([C:5]1[C:6]2[CH:7]=[N:8][N:9]([CH2:15][CH2:16][CH3:17])[C:10]=2[CH:11]=[C:12]([Br:14])[CH:13]=1)=[O:4].[CH3:1][O:2][C:3]([C:5]1[C:6]2[C:10]([CH:11]=[C:12]([Br:14])[CH:13]=1)=[N:9][N:8]([CH2:15][CH2:16][CH3:17])[CH:7]=2)=[O:4]

Participants

4

Reactant 2

HCID 78401-BromopropaneHCID 24728062methyl 6-bromo-1H-indazole-4-carboxylate

Product 2

HCID 674654456-bromo-2-propyl-2H-indazole-4-carboxylic acid methyl esterYield 20%HCID 67466712HCID 67466712, compoundYield 20%

Conditions

Temperature
40 °C

Procedure

The title compounds were prepared in the same manner as described for example 42 (step a) from 6-bromo-1H-indazole-4-carboxylic acid methyl ester (3.0 g, 11.66 mmol) and 1-propyl bromide (1.59 g, 12.94 mmol) wherein the contents were heated at 40° C. for 30 min. The obtained crude products were purified by silica gel chromatography (eluent: 10% ethyl acetate in petroleum ether) to afford the title compounds 6-bromo-1-propyl-1H-indazole-4-carboxylic acid methyl ester (700 mg, 20%) and undesired isomer 6-bromo-2-propyl-2H-indazole-4-carboxylic acid methyl ester (700 mg, 20%) as white solids. 1H NMR (400 MHz, DMSO-d6): (N1-propyl isomer): δ 0.83-0.80 δ (t, J=7.6, 3H), 1.84-1.81 (t, J=14.4 Hz, 2H), 3.95-3.94 (d, J=5.2 Hz 3H), 4.45-4.43 (t, 2H), 7.84 (d, J=1.2 Hz, 1H), 8.43 (d, J=14 Hz, 2H). LCMS (ES+): m/z=297.06.

Workup

  1. customThe title compounds were prepared in the same manner
  2. customThe obtained crude products
  3. customwere purified by silica gel chromatography (eluent: 10% ethyl acetate in petroleum ether)

Sources & evidence

ORD record
ord-6caf69ea39a34ebfad8e53675992da38
Source dataset
uspto-grants-2014_09
Patent number
US08846935B2

Reaction notes

Loading…