HCID 54403025, compound → HCID 86735837, compound

HRID 866449Notes

Reaction equation

HRID 866449 reaction equation
[CH2:1]([O:3][C:4](=[O:24])[C:5](=[N:20]OCC)[C:6]1[N:7]=[C:8]([NH:11][C:12]([O:14][CH2:15][C:16]([Cl:19])([Cl:18])[Cl:17])=[O:13])[S:9][CH:10]=1)[CH3:2].[H][H]>Cl.C(O)C.[Pd]>[ClH:17].[CH2:1]([O:3][C:4](=[O:24])[CH:5]([NH2:20])[C:6]1[N:7]=[C:8]([NH:11][C:12]([O:14][CH2:15][C:16]([Cl:17])([Cl:19])[Cl:18])=[O:13])[S:9][CH:10]=1)[CH3:2]

Participants

6

Reactant 2

HCID 54403025HCID 54403025, compoundHCID 178418361HCID 178418361, compound

Product 1

HCID 86735837HCID 86735837, compoundYield 144.1%

Reagents, catalysts & solvents 3

HCID 23938PalladiumCatalystHCID 313Hydrochloric AcidSolventHCID 702EthanolSolvent

Procedure

A solution of 10.45 g of α-ethoxyimino-α-[2-(trichloroethoxycarbonylamino)thiazol-4-yl]acetic acid ethyl ester in a mixture of 10% hydrochloric acid and ethanol is catalytic-hydrogenated over 8.0 of 5% palladium on charcoal at room temperature under atomospheric pressure. After the absorption of two equivalents of hydrogen, the catalyst in the reaction mixture is filtered off and the filtrate is concentrated to dryness under reduced pressure. By the procedure, 7.43 g of α-amino-α-[2-(trichloroethoxycarbonylamino)thiazol-4-yl]acetic acid ethyl ester hydrochloric acid salt is obtained (yield, 72%). This product is suspended in ethyl acetate and the obtained suspension is washed with saturated sodium bicarbonate aq. solution, washed with water and dried over anhydrous magnesium sulfate. The oily product obtained by the distillation of the solvent, is dissolved in 60 ml of N,N-dimethylformamide and, to the solution is added 4.2 g of tetramethylguanidine and then 3.94 g of t-butyloxycarbonylazide, followed by the stirring for 15 hours at room temperature. The reaction mixture is poured into water and extracted with ethyl acetate. The organic layer is washed with 1N hydrochloric acid and then saturated NaCl aq. solution and dried over anhydrous magnesium sulfate. The oily product obtained by the distillation of the solvent is purified by a column chromatography packed with silica gel. The procedure gives 4.06 g of α-t-butyloxycarbonylamino-α-[2-(trichloroethoxycarbonylamino)thiazol-4-yl]acetic acid ethyl ester (yield, 46.5%). Melting point: 94°-95° C.

Workup

  1. filtrationthe catalyst in the reaction mixture is filtered off
  2. concentrationthe filtrate is concentrated to dryness under reduced pressure

Sources & evidence

ORD record
ord-f1d3540dde494b52acdc1133ee1c9930
Source dataset
uspto-grants-1978_07
Patent number
US04098888

Reaction notes

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