Trifluoroacetic acid → HCID 68136757, compound

HRID 1657388Notes

Reaction equation

HRID 1657388 reaction equation
Br[CH2:2][C:3]([NH:5][C@@H:6]1[C:18](=[O:19])[N:8]2[C:9]([C:14]([O:16][CH3:17])=[O:15])=[C:10]([CH3:13])[CH2:11][S:12][C@H:7]12)=[O:4].P(Cl)(Cl)(Cl)(Cl)Cl.N1C2C(=CC=CC=2)C=CC=1.C[O-].[Li+].[Li].FC(F)(F)[C:42](O)=[O:43]>O1CCCC1.O.CO>[C:3]([NH:5][C@:6]1([O:43][CH3:42])[C:18](=[O:19])[N:8]2[C:9]([C:14]([O:16][CH3:17])=[O:15])=[C:10]([CH3:13])[CH2:11][S:12][C@H:7]12)(=[O:4])[CH3:2]

Participants

10

Reactant 6

HCID 6422Trifluoroacetic acidHCID 7047QuinolineHCID 24819Phosphorus pentachlorideHCID 3028194LithiumHCID 4177230Lithium methanolateHCID 131710261HCID 131710261, compound

Product 1

HCID 68136757HCID 68136757, compound

Reagents, catalysts & solvents 3

HCID 887MethanolSolvent2×HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent

Conditions

Temperature
-70 °C

Procedure

Methyl 7β-(2'-bromo-1'-chloroethylidenimino)-3-methyl-3-cephem-4-carboxylate was prepared from methyl 7β-bromoacetamido-3-methyl-3-cephem-4-carboxylate(1.34 g), phosphorus pentachloride(1.5 g) and quinoline(1 ml) according to the same procedure as in Example 23 - (1) and dissolved in tetrahydrofuran(80 ml). To this solution was added a methanol solution of lithium methoxide prepared from lithium(200 mg) and methanol(20 ml) at -70°C. The reaction mixture was stirred at -70°C. for 30 minutes, then trifluoroacetic acid(2.5 ml) was added and stirring was continued at room temperature for 10 minutes. The mixture was poured into water and extracted with ethyl acetate. The extracts were washed with 10 % dipotassium hydrogen phosphate solution and water, dried over sodium sulfate and evaporated under reduced pressure. The residue was chromatographed on silica gel to afford 250 mg of methyl 7β-acetamido-7α-methoxy-3-methyl-3-cephem-4-carboxylate. IR νmaxliquid cm -1 : 3220, 1770, 1730, 1690. NMR(CDCl3) δ ppm: 2.13(6H, singlet), 3.20 and 3.37(2H, AB-quartet, J=17 Hz), 3.55(3H, singlet), 3.83(3H, singlet), 5.07(1H, singlet), 7.52(1H, singlet).

Workup

  1. stirringstirring
  2. waitwas continued at room temperature for 10 minutes
  3. extractionextracted with ethyl acetate
  4. washThe extracts were washed with 10 % dipotassium hydrogen phosphate solution and water
  5. dry with materialdried over sodium sulfate
  6. customevaporated under reduced pressure
  7. customThe residue was chromatographed on silica gel

Sources & evidence

ORD record
ord-b35026ee82494e2dac2b39f16159d7b5
Source dataset
uspto-grants-1976_06
Patent number
US03960845

Reaction notes

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