Phosphorus oxychloride → Chloro-N,N-dimethylformiminium chloride
Reaction equation
P(Cl)(Cl)([Cl:3])=O.[CH:6]([NH:8][C:9]1[S:10][C:11]([Cl:28])=[C:12]([C:14](=[N:18][O:19][CH2:20][C:21]([O:23][C:24]([CH3:27])([CH3:26])[CH3:25])=[O:22])[C:15]([OH:17])=O)[N:13]=1)=[O:7].[CH3:29][N+:30]([CH3:33])=[CH:31][Cl:32].[Cl-].C[Si](C)(C)NC(=O)C.[NH2:43][CH:44]1[C:61](=[O:62])[N:46]2[C:47]([C:58]([OH:60])=[O:59])=[C:48]([CH2:51][S:52][C:53]3[S:54][CH:55]=[N:56][N:57]=3)[CH2:49][S:50][C@H:45]12>C(OCC)(=O)C.O1CCCC1.O.CN(C)C=O>[CH3:29][N+:30]([CH3:33])=[CH:31][Cl:32].[Cl-:3].[CH:6]([NH:8][C:9]1[S:10][C:11]([Cl:28])=[C:12]([C:14](=[N:18][O:19][CH2:20][C:21]([O:23][C:24]([CH3:27])([CH3:26])[CH3:25])=[O:22])[C:15]([NH:43][CH:44]2[C:61](=[O:62])[N:46]3[C:47]([C:58]([OH:60])=[O:59])=[C:48]([CH2:51][S:52][C:53]4[S:54][CH:55]=[N:56][N:57]=4)[CH2:49][S:50][C@H:45]23)=[O:17])[N:13]=1)=[O:7]Participants
Reactant 5
Product 2
Reagents, catalysts & solvents 4
Procedure
Vilsmeier reagent was prepared from phosphorus oxychloride (1.2 g) and N,N-dimethylformamide (0.6 g) in ethyl acetate (2.4 ml) in a usual manner. 2-(2-Formamido-5-chlorothiazol-4-yl)-2-tert-butoxycarbonylmethoxyiminoacetic acid (syn isomer) (2.4 g) was added to the stirred suspension of Vilsmeier reagent in dry tetrahydrofuran (24 ml) under ice-cooling and stirred for 20 minutes at same temperature [Solution A]. N-Trimethylsilylacetamide (6.4 g) was added to the stirred suspension of 7-amino-3-(1,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylic acid (2.0 g) in tetrahydrofuran (40 ml), and the mixture was stirred for 30 minutes at 35° to 40° C. To the solution was added the solution [Solution A] at -10° C., and the resulting solution was stirred at same temperature for 30 minutes. Water and ethyl acetate were added to the reaction mixture at -10° C. The organic layer was separated and added to water. The mixture was adjusted to pH 7.5 with a saturated aqueous solution of sodium bicarbonate. The aqueous layer was separated and adjusted to pH 2.0 with 10% aqueous hydrochloric acid, and then extracted with ethyl acetate. The extract was washed with a saturated aqueous solution of sodium chloride, dried over magnesium sulfate and evaporated in vacuo to give 7-[2-(2-formamido-5-chlorothiazol-4-yl)-2-tert-butoxycarbonylmethoxyiminoacetamido]-3-(1,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylic acid (syn isomer) (3.72 g).
Workup
- temperaturecooling
- stirringthe resulting solution was stirred at same temperature for 30 minutes
- customThe organic layer was separated
- additionadded to water
- customThe aqueous layer was separated
- extractionextracted with ethyl acetate
- washThe extract was washed with a saturated aqueous solution of sodium chloride
- dry with materialdried over magnesium sulfate
- customevaporated in vacuo
Sources & evidence
- ORD record
- ord-4b6c922bd3a44499becec796ea311308
- Source dataset
- uspto-grants-1984_03
- Patent number
- US04438113
Reaction notes
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