Thionyl Chloride → 2-(2-Formamidothiazol-4-yl)-2-methoxyiminoacetyl chloride

HRID 1905245Notes

Reaction equation

[CH:1]([NH:3][C:4]1[S:5][CH:6]=[C:7]([C:9](=[N:13][O:14][CH3:15])[C:10](O)=[O:11])[N:8]=1)=[O:2].S(Cl)([Cl:18])=O>CN(C)C=O>[CH:1]([NH:3][C:4]1[S:5][CH:6]=[C:7]([C:9](=[N:13][O:14][CH3:15])[C:10]([Cl:18])=[O:11])[N:8]=1)=[O:2]

Participants

Conditions

Temperature: 60 °C

Procedure

N,N-Dimethylformamide (3 drops) was added to a suspension of 2-(2-formamidothiazol-4-yl)-2-methoxyiminoacetic acid (syn isomer, 23 g.) in thionyl chloride (230 ml.), and stirred, at 60° C. for 5 minutes. After concentrating the solution in vaco, benzene was added to the residue. The presipitates were collected by filtration, washed with benzene (30 ml.) three times and diethyl ether in turn to give 2-(2-formamidothiazol-4-yl)-2-methoxyiminoacetyl chloride (anti isomer, 18 g.). On the other hand, trimethylsilylacetamide (46 g.) was added to a suspension of 4-nitrobenzyl 7-amino-3-cephem-4-carboxylate (16.8 g.) in methylene chloride (168 ml.), and stirred at 40° C. for an hour. To the suspension was gradually added 2-(2-formamidothiazol-4-yl)-2-methoxyiminoacetyl chloride (anti isomer, 13.6 g.) at -5° to 0° C., and stirred at the same temperature for an hour. Water (150 ml.) was added to the resultant solution and stirred for 15 minutes. The recipitates were collected by filtration, washed with water and dried over phosphorus pentoxide under reduced pressure to give 4-nitrobenzyl 7-[2-(2-formamidothiazol-4-yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylate (anti isomer, 25.7 g.).

Workup

concentrationAfter concentrating the solution in vaco, benzene
additionwas added to the residue
filtrationThe presipitates were collected by filtration
washwashed with benzene (30 ml.) three times and diethyl ether in turn

Sources & evidence

ORD record: ord-3022d933bc4944888b36a11c76984778
Source dataset: uspto-grants-1989_06
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US04841062

Reaction notes

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