Water → Ampicillin

HRID 1607977Notes

Reaction equation

HRID 1607977 reaction equation
[OH-].[Na+].O.[CH3:4][C:5]1([CH3:27])[S:9][C@@H:8]2[C@H:10]([NH:13][C:14]([C@H:16]([NH2:23])[C:17]3[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=3)=[O:15])[C:11](=[O:12])[N:7]2[C@H:6]1[C:24]([OH:26])=[O:25].O.O.O>S([O-])(O)(=O)=O.C([N+](CCCC)(CCCC)CCCC)CCC.C(Cl)Cl>[CH3:4][C:5]1([CH3:27])[S:9][C@@H:8]2[C@H:10]([NH:13][C:14]([C@H:16]([NH2:23])[C:17]3[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=3)=[O:15])[C:11](=[O:12])[N:7]2[C@H:6]1[C:24]([OH:26])=[O:25]

Participants

6

Reactant 3

HCID 962WaterHCID 14798Sodium Hydroxide2×HCID 23565Ampicillin Trihydrate

Product 1

HCID 6249Ampicillin

Reagents, catalysts & solvents 2

HCID 94433Tetrabutylammonium hydrogen sulfateCatalystHCID 6344DichloromethaneSolvent

Procedure

Tetrabutylammonium hydrogen sulfate (33.9 g, 0.10 mole) and 50 ml of 2N NaOH were combined with 200 ml H2O. The resulting pH was about 6.8. With stirring, CH2Cl2 (300 ml) and then ampicillin trihydrate (33.9 g, 0.10 mole) were added, and the pH adjusted from 4.5 to 8.5 with 53 ml 2N NaOH. The layers were separated and the aqueous layer extracted 4×200 ml CH2Cl2. The five organic layers were combined and evaporated to dryness in vacuo to yield the tetrabutylammonium salt of ampicillin, 54.1 g, 91.7%. Methyl acetoacetate (200 ml) was added to the salt and the water formed in the reaction removed by evaporation using a bath at 35° and a pressure of 5 mm. After one hour, title product began to crystallize. After 1.75 hour, 600 ml of ethyl acetate and 200 ml of hexane were added. After cooling to 0°-5°, title product was recovered by filtration, 53.5 g, 84.8% from salt, 77.8% overall from ampicillin; 1H-nmr (CDCl3) delta: 7.2 (m), 5.6-5.0 (m), 4.5 (s), 4.2 (s), 3.55 (s), 3.4-2.9 (m), 1.8 (s), 1.7-0.8 (m).

Workup

  1. customThe layers were separated
  2. extractionthe aqueous layer extracted 4×200 ml CH2Cl2
  3. customevaporated to dryness in vacuo

Sources & evidence

ORD record
ord-db1a4a1ca89244fabea3e3a48e57f9f9
Source dataset
uspto-grants-1989_09
Patent number
US04868297

Reaction notes

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