Acetic Acid → HCID 53700966, compound
Reaction equation
[N+:1]([CH2:3][C:4]([O:6][CH2:7][CH3:8])=[O:5])#[C-:2].[S:9]1[CH2:14][C:13](=O)[CH2:12][S:11][CH2:10]1.C(O)(=[O:18])C>O1CCCC1>[CH:2]([NH:1][C:3](=[C:13]1[CH2:12][S:11][CH2:10][S:9][CH2:14]1)[C:4]([O:6][CH2:7][CH3:8])=[O:5])=[O:18]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 0 °C
Procedure
A solution of potassium tert.-butylate (27.2 g) in tetrahydrofurane (200 cc) is cooled to 0° C. A solution of ethyl isocyanoacetate (25 g) in tetrahydrofurane (150 cc) is added dropwise. The mixture is stirred for a further one hour at 0° C. and a solution of 1,3-dithiacyclohexan-5-one (29.6 g) in tetrahydrofurane (375 cc) is then added. The reaction mixture is stirred for a further 90 minutes at 0° C. Acetic acid (50 cc) is added and the precipitate is filtered off. The solvents are evaporated off under reduced pressure (20 mm Hg) at 30° C. The residue is taken up with methylene chloride (2,500 cc). Extraction is carried out with a mixture of water (500 cc) and a saturated aqueous solution of sodium bicarbonate (300 cc). The organic phase is again washed with water (500 cc) and dried over sodium sulphate. The solution is treated with decolorising charcoal, filtered and then concentrated to dryness under reduced pressure (20 mm Hg) at 30° C. The residue is vigorously stirred with ethyl ether (400 cc). The precipitate obtained is filtered off. Ethyl α-formylamino-(4,5-dihydro-1,3-dithiin-5-ylidene)-acetate (18.5 g) is thus obtained. The filtrate is concentrated to dryness under reduced pressure (20 mm Hg) at 20° C. The residue is purified by chromatography on a column (diameter 3.7 cm; height 47 cm) containing silica (250 g). Elution is carried out with a mixture (two liters) of methylene chloride and ethyl acetate (85/15 by volume). A mixture (4.4 g) of ethyl α-formylamino-(4,5-dihydro-1,3-dithiin-5-ylidene)-acetate and ethyl α-formylamino-(1,3-dithiin-5-yl)-acetate is thus obtained.
Workup
- stirringThe reaction mixture is stirred for a further 90 minutes at 0° C
- filtrationthe precipitate is filtered off
- customThe solvents are evaporated off under reduced pressure (20 mm Hg) at 30° C
- extractionExtraction
- additionis carried out with a mixture of water (500 cc)
- washThe organic phase is again washed with water (500 cc)
- dry with materialdried over sodium sulphate
- additionThe solution is treated with decolorising charcoal
- filtrationfiltered
- concentrationconcentrated to dryness under reduced pressure (20 mm Hg) at 30° C
- stirringThe residue is vigorously stirred with ethyl ether (400 cc)
- customThe precipitate obtained
- filtrationis filtered off
Sources & evidence
- ORD record
- ord-7fb7c65c46e54c5a8d00884cc1691e50
- Source dataset
- uspto-grants-1979_12
- Patent number
- US04178290
Reaction notes
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