Hydrochloric Acid → 2-(2-Aminothiazol-4-yl)-2-benzyloxyiminoacetic acid

HRID 894748Notes

Reaction equation

HRID 894748 reaction equation
[NH2:1][C:2]1[S:3][CH:4]=[C:5]([C:7](=[N:13][O:14][CH2:15][C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=2)[C:8]([O:10]CC)=[O:9])[N:6]=1.[OH-].[Na+].CO.Cl>O1CCCC1>[NH2:1][C:2]1[S:3][CH:4]=[C:5]([C:7](=[N:13][O:14][CH2:15][C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=2)[C:8]([OH:10])=[O:9])[N:6]=1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 887MethanolHCID 14798Sodium HydroxideHCID 54194304Ethyl 2-(2-aminothiazol-4-yl)-2-benzyloxyiminoacetate

Product 1

HCID 541725632-(2-Aminothiazol-4-yl)-2-benzyloxyiminoacetic acidYield 36.2%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

A mixture of ethyl 2-(2-aminothiazol-4-yl)-2-benzyloxyiminoacetate (syn isomer, 35 g.), 1 N aqueous sodium hydroxide (172 ml.), methanol (150 ml.) and tetrahydrofuran (150 ml.) was stirred at 35° to 40° C. for 9 hours and at room temperature for 12 hours. After adjusted the resultant solution to pH 6.5 with conc. hydrochloric acid, the solution was concentrated to about 2/3 volume of the initial. The concentrate was adjusted to pH 3.5 with conc. hydrochloric acid under ice cooling, and the precipitates were collected by filtration, washed with water and acetone in turn and then dried over phosphorus pentoxide under reduced pressure to give 2-(2-aminothiazol-4-yl)-2-benzyloxyiminoacetic acid (syn isomer, 11.5 g.).

Workup

  1. concentrationthe solution was concentrated to about 2/3 volume of the initial
  2. filtrationthe precipitates were collected by filtration
  3. washwashed with water and acetone in turn
  4. dry with materialdried over phosphorus pentoxide under reduced pressure

Sources & evidence

ORD record
ord-a99336a492694495a8da835f191f4f1a
Source dataset
uspto-grants-1981_08
Patent number
US04284631

Reaction notes

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