Diethyl Oxalate → HCID 69968502, compound

HRID 1166213Notes

Reaction equation

HRID 1166213 reaction equation
[Cl:1][C:2]1[S:6][C:5](Cl)=[C:4]([Cl:8])[C:3]=1[Cl:9].C([Li])CCC.[C:15](OCC)(=[O:21])[C:16]([O:18][CH2:19][CH3:20])=[O:17]>>[CH2:19]([O:18][C:16](=[O:17])[C:15]([C:5]1[S:6][C:2]([Cl:1])=[C:3]([Cl:9])[C:4]=1[Cl:8])=[O:21])[CH3:20]

Participants

4

Reactant 3

HCID 7268Diethyl OxalateHCID 22344TetrachlorothiopheneHCID 178418339Butyllithium

Product 1

HCID 69968502HCID 69968502, compoundYield 47%

Conditions

Temperature
-18 °C

Procedure

To tetrachlorothiophene (2.0 g, 9.0 mmol) in an oven dried 50 mL flask, evacuated and flushed with nitrogen, was added anhydrous diethyl ether (12 ml). The resulting solution was cooled to −18° C., then n-butyllithium (1.6 M in hexane) (5.6 ml, 9.0 mmol) was added dropwise via a syringe. After stirring for 10 min at −18° C., diethyl oxalate (1.4 ml, 9.9 mmol) was added dropwise. Stirring was continued for 30 min, then the reaction mixture was quenched with 1N HCl. The organic layer was separated, dried over Na2SO4 and concentrated under vacuum. Purification was performed by column chromatography using hexane/ethyl acetate (20:1) to provide (3,4,5-trichlorothiophen-2-yl)-oxo-acetic acid ethyl ester as a yellow solid (0.93 g, 47%). MS (M+H)+: 288.92; 1H NMR (300 MHz, CDCl3) δ4.44 (2H, q, J=7.1 Hz), 1.43 (3H, t, J=7.1 Hz). 13C NMR (75 MHz, CDCl3) δ173.72, 161.82, 136.83, 133.16, 127.30, 126.53, 63.76, 14.11.

Workup

  1. customevacuated
  2. customflushed with nitrogen
  3. additionwas added anhydrous diethyl ether (12 ml)
  4. stirringStirring
  5. waitwas continued for 30 min
  6. customthe reaction mixture was quenched with 1N HCl
  7. customThe organic layer was separated
  8. dry with materialdried over Na2SO4
  9. concentrationconcentrated under vacuum
  10. customPurification

Sources & evidence

ORD record
ord-d4cce2bd0c8d4ac881582b3444a8c970
Source dataset
uspto-grants-2003_09
Patent number
US06613786B2

Reaction notes

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