Methylamine → Ethyl 1-(methylamino)isoquinoline-7-carboxylate

HRID 880975Notes

Reaction equation

HRID 880975 reaction equation
CN.O1CCCC1.Cl[C:9]1[C:18]2[C:13](=[CH:14][CH:15]=[C:16]([C:19]([O:21][CH2:22][CH3:23])=[O:20])[CH:17]=2)[CH:12]=[CH:11][N:10]=1.COC1C=CC([CH2:30][NH:31]C2C3C(=CC=C(C(O)=O)C=3)C=CN=2)=CC=1>>[CH3:30][NH:31][C:9]1[C:18]2[C:13](=[CH:14][CH:15]=[C:16]([C:19]([O:21][CH2:22][CH3:23])=[O:20])[CH:17]=2)[CH:12]=[CH:11][N:10]=1

Participants

5

Reactant 4

HCID 6329Methylamine2×HCID 8028TetrahydrofuranHCID 674916931-(4-Methoxybenzylamino)isoquinoline-7-carboxylic acidHCID 86664617Ethyl 1-chloroisoquinoline-7-carboxylate

Product 1

HCID 67491404Ethyl 1-(methylamino)isoquinoline-7-carboxylateYield 85%

Conditions

Temperature
60 °C

Procedure

A solution of methylamine in tetrahydrofuran (30 mL, 60 mmol, 2 M) was added to ethyl 1-chloroisoquinoline-7-carboxylate (formed in Step 3 of Intermediate 27) (705 mg, 2.99 mmol) in a sealed tube. The reaction was heated to 60° C. and stirred overnight. LCMS indicated the reaction was not complete. Additional methylamine (10 mL, 20 mmol, 2 M in THF) was added and the reaction was heated to 60° C. for another 18 hours. The reaction was cooled to room temperature and concentrated. The residue was partitioned between water and dichloromethane. The organic layer was dried over magnesium sulphate, filtered, and concentrated. Purification by flash column chromatography (25-65% ethyl acetate/heptanes) gave the title compound (584 mg, 85%) as a yellow oil that solidified upon standing. +ESI (M+H) 231.1; 1H NMR (400 MHz, DMSO-d6, δ): 8.83-8.94 (m, 1H), 8.07 (dd, J=8.58, 1.56 Hz, 1H), 7.99 (d, J=5.85 Hz, 1H), 7.89 (d, J=4.49 Hz, 1H), 7.77 (d, J=8.58 Hz, 1H), 6.92 (d, J=5.07 Hz, 1H), 4.38 (q, J=7.02 Hz, 2H), 2.97 (d, J=4.49 Hz, 3H), 1.38 (t, J=7.12 Hz, 3H).

Workup

  1. temperaturethe reaction was heated to 60° C. for another 18 hours
  2. temperatureThe reaction was cooled to room temperature
  3. concentrationconcentrated
  4. customThe residue was partitioned between water and dichloromethane
  5. dry with materialThe organic layer was dried over magnesium sulphate
  6. filtrationfiltered
  7. concentrationconcentrated
  8. customPurification by flash column chromatography (25-65% ethyl acetate/heptanes)

Sources & evidence

ORD record
ord-84cec0cd5590481687db87a8606afd11
Source dataset
uspto-grants-2015_03
Patent number
US08993586B2

Reaction notes

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