Phosphorus oxychloride → Chloro-N,N-dimethylformiminium chloride
Reaction equation
P(Cl)(Cl)([Cl:3])=O.[CH:6]([NH:8][C:9]1[S:10][CH:11]=[C:12]([C:14](=[N:18][O:19][CH2:20][CH2:21][CH2:22][NH:23][C:24]([O:26][C:27]([CH3:30])([CH3:29])[CH3:28])=[O:25])[C:15]([OH:17])=O)[N:13]=1)=[O:7].[CH3:31][N+:32]([CH3:35])=[CH:33][Cl:34].[Cl-].C[Si](CC(N)=O)(C)C.[NH2:45][CH:46]1[C:56](=[O:57])[N:48]2[C:49]([C:53]([OH:55])=[O:54])=[CH:50][CH2:51][S:52][C@H:47]12>C(OCC)(=O)C.O.CN(C)C=O>[CH3:31][N+:32]([CH3:35])=[CH:33][Cl:34].[Cl-:3].[CH:6]([NH:8][C:9]1[S:10][CH:11]=[C:12]([C:14](=[N:18][O:19][CH2:20][CH2:21][CH2:22][NH:23][C:24]([O:26][C:27]([CH3:30])([CH3:29])[CH3:28])=[O:25])[C:15]([NH:45][CH:46]2[C:56](=[O:57])[N:48]3[C:49]([C:53]([OH:55])=[O:54])=[CH:50][CH2:51][S:52][C@H:47]23)=[O:17])[N:13]=1)=[O:7]Participants
Reactant 5
Product 2
Reagents, catalysts & solvents 3
Procedure
Vilsmeier reagent was prepared from N,N-dimethylformamide (0.6 g.) and phosphoryl chloride (1.2 g.) in an usual manner. 2-(2-Formamidothiazol-4-yl)-2-(3-tert-butoxycarbonylaminopropoxyimino)acetic acid (syn isomer, 2.6 g.) was added to a stirred suspension of the Vilsmeier reagent in ethyl acetate (30 ml.) under ice-cooling and stirred at the same temperature for 30 minutes [hereinafter referred to solution A]. Trimethylsilylacetamide (5.5 g.) was added to a stirred suspension of 7-amino-3-cephem-4-carboxylic acid (1.4 g.) in ethyl acetate (20 ml.), and the mixture was stirred at 40° C. for 30 minutes. The solution A was added to the solution at -10° to -30° C. and stirred at the same temperature for an hour. Water and ethyl acetate (100 ml.) were added to the reaction mixture at -10° C. and the ethyl acetate layer was separated. Water was added to the ethyl acetate layer, and adjusted to pH 7.5 with a sodium bicarbonate saturated aqueous solution. The aqueous solution was separated and ethyl acetate was added thereto. The mixture was adjusted to pH 2.8 with 10% hydrochloric acid under ice-cooling. The ethyl acetate layer was separated, washed with a sodium chloride saturated aqueous solution and dried over magnesium sulfate. The solution was concentrated in vacuo, and the residue was pulverized with diisopropyl ether to give 7-[2-(2-formamidothiazol-4-yl)-2-(3-tert-butoxycarbonylaminopropoxyimino)acetamido]-3-cephem-4-carboxylic acid (syn isomer, 2.2 g.)
Workup
- temperaturecooling
- stirringthe mixture was stirred at 40° C. for 30 minutes
- stirringstirred at the same temperature for an hour
- customthe ethyl acetate layer was separated
- additionWater was added to the ethyl acetate layer
- customThe aqueous solution was separated
- additionethyl acetate was added
- temperaturecooling
- customThe ethyl acetate layer was separated
- washwashed with a sodium chloride saturated aqueous solution
- dry with materialdried over magnesium sulfate
- concentrationThe solution was concentrated in vacuo
Sources & evidence
- ORD record
- ord-c51f331ecfba4bfdadfd82dd816a80a7
- Source dataset
- uspto-grants-1981_08
- Patent number
- US04284631
Reaction notes
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