Triethylamine → 4-Chloro-6-fluoro-1-(4-methoxy-benzyl)-2-oxo-1,2-dihydro-[1,8]-naphthyridine-3-carboxylic Acid Ethyl Ester

HRID 901255Notes

Reaction equation

HRID 901255 reaction equation
[CH2:1]([O:3][C:4]([C:6]1[C:7](=[O:27])[N:8]([CH2:18][C:19]2[CH:24]=[CH:23][C:22]([O:25][CH3:26])=[CH:21][CH:20]=2)[C:9]2[C:14]([C:15]=1O)=[CH:13][C:12]([F:17])=[CH:11][N:10]=2)=[O:5])[CH3:2].C(N(CC)CC)C.O=P(Cl)(Cl)[Cl:37]>>[CH2:1]([O:3][C:4]([C:6]1[C:7](=[O:27])[N:8]([CH2:18][C:19]2[CH:24]=[CH:23][C:22]([O:25][CH3:26])=[CH:21][CH:20]=2)[C:9]2[C:14]([C:15]=1[Cl:37])=[CH:13][C:12]([F:17])=[CH:11][N:10]=2)=[O:5])[CH3:2]

Participants

4

Reactant 3

HCID 8471TriethylamineHCID 24813Phosphorus oxychlorideHCID 692163256-Fluoro-4-hydroxy-1-(4-methoxy-benzyl)-2-oxo-1,2-dihydro-[1,8]-naphthyridine-3-carboxylic Acid Ethyl Ester

Product 1

HCID 692183544-Chloro-6-fluoro-1-(4-methoxy-benzyl)-2-oxo-1,2-dihydro-[1,8]-naphthyridine-3-carboxylic Acid Ethyl EsterYield 85%

Procedure

A solution of 6-fluoro-4-hydroxy-1-(4-methoxy-benzyl)-2-oxo-1,2-dihydro-[1,8]-naphthyridine-3-carboxylic acid ethyl ester (74) (7.0 g, 18.79 mmol) and triethylamine (5.2 mL, 37.58 mmol) was heated in neat POCl3 at 90° C. for 3 h. The solution was cooled and the excess POCl3 was distilled under vacuum. The residue was suspended in saturated NaHCO3 solution, sonicated briefly and filtered. The solids were dissolved in dichloromethane, washed subsequently by saturated NaHCO3 solution, water and brine. The organic phase was dried over MgSO4 and evaporated to yield 6.2 g (85%) of 4-chloro-6-fluoro-1-(4-methoxy-benzyl)-2-oxo-1,2-dihydro-[1,8]-naphthyridine-3-carboxylic acid ethyl ester (76) as yellow waxy solids. 1H-NMR (DMSO-d6): δ 1.31 (t, J=7.2 Hz, 3H), 3.70 (s, 3H), 4.37 (q, J=7.2 Hz, 2H), 5.51 (s, 2H), 6.84 (m, 2H), 7.24 (m, 2H), 8.37 (dd, J=2.8, 8.0 Hz, 1H), 8.82 (d, J=2.8 Hz, 1H); EIMS: 391 (M+1).

Workup

  1. temperatureThe solution was cooled
  2. distillationthe excess POCl3 was distilled under vacuum
  3. customsonicated briefly
  4. filtrationfiltered
  5. dissolutionThe solids were dissolved in dichloromethane
  6. washwashed subsequently by saturated NaHCO3 solution, water and brine
  7. dry with materialThe organic phase was dried over MgSO4
  8. customevaporated

Sources & evidence

ORD record
ord-a193a5e2a9f34e47a7efd8a348b1e86e
Source dataset
uspto-grants-2008_04
Patent number
US07361760B2

Reaction notes

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