Ammonium formate → tert-butyl 7-(4-hydroxy-2-oxopyridin-1(2H)-yl)-5-methyl-3,4-dihydro-1H-pyrido[4,3-b]indole-2(5H)-carboxylate

HRID 1020656Notes

Reaction equation

HRID 1020656 reaction equation
C([O:8][C:9]1[CH:14]=[CH:13][N:12]([C:15]2[CH:16]=[CH:17][C:18]3[C:19]4[CH2:28][N:27]([C:29]([O:31][C:32]([CH3:35])([CH3:34])[CH3:33])=[O:30])[CH2:26][CH2:25][C:20]=4[N:21]([CH3:24])[C:22]=3[CH:23]=2)[C:11](=[O:36])[CH:10]=1)C1C=CC=CC=1.C([O-])=O.[NH4+]>CO.[Pd]>[OH:8][C:9]1[CH:14]=[CH:13][N:12]([C:15]2[CH:16]=[CH:17][C:18]3[C:19]4[CH2:28][N:27]([C:29]([O:31][C:32]([CH3:34])([CH3:33])[CH3:35])=[O:30])[CH2:26][CH2:25][C:20]=4[N:21]([CH3:24])[C:22]=3[CH:23]=2)[C:11](=[O:36])[CH:10]=1

Participants

5

Conditions

Temperature
90 °C

Procedure

To a solution of tert-butyl 7-(4-(benzyloxy)-2-oxopyridin-1(2H)-yl)-5-methyl-3,4-dihydro-1H-pyrido[4,3-b]indole-2(5H)-carboxylate (0.98 g, 2.0 mmol) in CH3OH (30 mL) was added 5% Pd/C (0.3 g) and ammonium formate (0.32 g, 5.1 mmol) under an atmosphere of argon. The reaction was stirred at 90° C. until complete. The reaction mixture was cooled and filtered through a layer of Celite. The solvent was removed under reduced pressure to give tert-butyl 7-(4-hydroxy-2-oxopyridin-1(2H)-yl)-5-methyl-3,4-dihydro-1H-pyrido[4,3-b]indole-2(5H)-carboxylate, which was used directly in the next step. To a solution of tert-butyl 7-(4-hydroxy-2-oxopyridin-1(2H)-yl)-5-methyl-3,4-dihydro-1H-pyrido[4,3-b]indole-2(5H)-carboxylate (800 mg, 2.02 mmol) in THF (10 mL) was added LiN(SiMe3)2 (1.0 M in THF, 2.6 mL, 2.6 mmol) followed by PhN(Tf)2 (0.94 g, 2.6 mmol) under an atmosphere of argon. The reaction was stirred at room temperature until complete. The solvent was removed under reduced pressure, and the residue was purified by flash column chromatography (silica gel, hexanes/EtOAc, 1:1) to give the title compound (0.42 g, 40% yield) as a white solid: 1H NMR (300 MHz, CDCl3) δ 7.57-7.53 (m, 2H), 7.30 (d, J=1.5 Hz, 1H), 7.02-6.99 (m, 1H), 6.60 (d, J=2.7 Hz, 1H), 6.27 (dd, J=7.8, 2.7 Hz, 1H), 4.65 (s, 2H), 3.85 (m, 2H), 3.65 (s, 3H), 2.84 (m, 2H), 1.51 (s, 9H); ESI MS m/z 528 [M+H]+.

Workup

  1. temperatureThe reaction mixture was cooled
  2. filtrationfiltered through a layer of Celite
  3. customThe solvent was removed under reduced pressure

Sources & evidence

ORD record
ord-a5e8bf6918a74744a8b41b34540c1e9e
Source dataset
uspto-grants-2014_05
Patent number
US08716308B2

Reaction notes

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