Phosphorus oxychloride → Diethyl 6-chloro-5-nitro-2,3-pyridinedicarboxylate

HRID 864898

Reaction equation

HRID 864898 reaction equation
[N+:1]([C:4]1[C:9](=O)[NH:8][C:7]([C:11]([O:13][CH2:14][CH3:15])=[O:12])=[C:6]([C:16]([O:18][CH2:19][CH3:20])=[O:17])[CH:5]=1)([O-:3])=[O:2].P(Cl)(Cl)([Cl:23])=O>>[Cl:23][C:9]1[N:8]=[C:7]([C:11]([O:13][CH2:14][CH3:15])=[O:12])[C:6]([C:16]([O:18][CH2:19][CH3:20])=[O:17])=[CH:5][C:4]=1[N+:1]([O-:3])=[O:2]

Participants

3

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 19958208Diethyl 1,6-dihydro-5-nitro-6-oxo-2,3-pyridinedicarboxylate

Product 1

HCID 15451784Diethyl 6-chloro-5-nitro-2,3-pyridinedicarboxylateYield 73.9%

Conditions

Temperature
80 °C

Procedure

Diethyl 1,6-dihydro-5-nitro-6-oxo-2,3-pyridinedicarboxylate (26.23 g, 0.092 mol) is partially dissolved under N2 atmosphere in 250 mL of phosphorous oxychloride and the mixture is heated to 80° C. for 15 hours. The mixture is cooled and concentrated and the resulting oil dissolved in ethyl acetate and washed with water, 10% K2CO3 and brine. The organic layer is dried over MgSO4, filtered and the solvent removed to yield a solid which is recrystallized from absolute ethanol/water to give 20.65 g of the product as a brown solid in 73.9% yield, having a melting point of 84.5°-86° C.

Workup

  1. temperatureThe mixture is cooled
  2. concentrationconcentrated
  3. dissolutionthe resulting oil dissolved in ethyl acetate
  4. washwashed with water, 10% K2CO3 and brine
  5. dry with materialThe organic layer is dried over MgSO4
  6. filtrationfiltered
  7. customthe solvent removed
  8. customto yield a solid which
  9. customis recrystallized from absolute ethanol/water

Sources & evidence

ORD record
ord-5cf7c0670f8a4720a17e375270347a72
Source dataset
uspto-grants-1996_10
Patent number
US05565411

Linked notes

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