Phosphorus oxychloride → Chloro-N,N-dimethylformiminium chloride
Reaction equation
P(Cl)(Cl)([Cl:3])=O.FC(F)(F)C(NC1SC(Cl)=C(C(=NOCC#C)C(O)=O)N=1)=O.[CH3:28][N+:29]([CH3:32])=[CH:30][Cl:31].[Cl-].C[Si](CC(N)=O)(C)C.[CH3:42][C:43]([O:45][CH2:46][C:47]1[CH2:56][S:55][C@@H:50]2[C@H:51](N)[C:52](=[O:53])[N:49]2[C:48]=1[C:57]([OH:59])=[O:58])=[O:44]>C(OCC)(=O)C.O1CCCC1.O.CN(C)C=O>[CH3:28][N+:29]([CH3:32])=[CH:30][Cl:31].[Cl-:3].[CH3:42][C:43]([O:45][CH2:46][C:47]1[CH2:56][S:55][C@@H:50]2[CH2:51][C:52](=[O:53])[N:49]2[C:48]=1[C:57]([OH:59])=[O:58])=[O:44]Participants
Reactant 5
Product 2
Reagents, catalysts & solvents 4
Procedure
Vilsmeier reagent was prepared from phosphorus oxychloride (1.1 g) and N,N-dimethylformamide (0.5 g) in ethyl acetate (2.0 ml) in a conventional manner. 2-[2-(2,2,2-Trifluoroacetamido)-5-chlorothiazol-4-yl]-2-propargyloxyiminoacetic acid (syn isomer, 2.2 g) was added to the stirred suspension of Vilsmeier reagent in tetrahydrofuran (22 ml) under ice cooling and stirred for 20 minutes at same temperature [Solution A]. Trimethylsilylacetamide (5.1 g) was added to the stirred suspension of 7-aminocephalosporanic acid (1.5 g) in tetrahydrofuran (30 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 the 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% 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 under reduced pressure to give 7-[2-(2,2,2-trifluoroacetamido)-5-chlorothiazol-4-yl]-2-propargyloxyiminoacetamido]cephalosporanic acid (syn isomer, 2.51 g).
Workup
- stirringthe resulting solution was stirred at the 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 under reduced pressure
Sources & evidence
- ORD record
- ord-8c9c58b50fc54864883c78fccbd929cf
- Source dataset
- uspto-grants-1984_03
- Patent number
- US04438113
Reaction notes
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