Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Triethylamine | HCID 8471 | — |
| Reactant | Ethyl 3-aminobenzoate | HCID 11400 | — |
| Reactant | Thionyl Chloride | HCID 24386 | — |
| Reactant | 2-Methyl-5,6-dihydro-1,4-oxathiine-3-carboxylic acid | HCID 539946 | — |
| Solvent | Dichloromethane | HCID 6344 | — |
| Product | HCID 507307 | HCID 507307 | 73% |
Reaction Steps
Thionyl chloride (6.5 g, 0.055 mole) was added to a stirred mixture of 5,6-dihydro-2-methyl-1,4-oxathiin-3-carboxylic acid (8.0 g, 0.050 mole) and methylene chloride (50 ml). The mixture was warmed to 35°-40° C. for hours and the resulting dark solution evaporated under reduced pressure. The solid residue, crude 5,6-dihydro-2-methyl-1,4-oxathiin-3-carbonyl chloride, was dissolved in methylene chloride (50 ml). On the following day, the solution was treated dropwise at 5°-20° C. over 2 hours with a solution of ethyl 3-aminobenzoate (8.2 g, 0.050 mole) and triethylamine (5.5 g, 0.054 mole) in methylene chloride (50 ml). The reaction mixture was stirred at room temperature for a further 5 hours and worked up by washing in sequence with water (50 ml), dilute hydrochloric acid (3.5%, 50 ml), water (50 ml), dilute sodium hydroxide (2%, 25 ml) and water (50 ml). Evaporation of the solvent left an oil, which slowly solidified. Recrystallization from ethanol 75 ml gave yellow-tan crystals, m.p. 100° -102° C. (11.2 g, 73% yield).
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US05268389 |
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| Source dataset | uspto-grants-1993_12 |
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| ORD ID | ord-7f7d693bea1e4d1d8a24409909fbe53a |
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| Source note | uspto-grants-1993_12 |
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