Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Triethylamine | HCID 8471 | — |
| Reactant | 1,3-Cyclohexanedione | HCID 10434 | — |
| Reactant | Oxalyl chloride | HCID 65578 | — |
| Reactant | HCID 14851228 | HCID 14851228 | — |
| Catalyst | Dimethylformamide | HCID 6228 | — |
| Solvent | Dichloromethane | HCID 6344 | — |
| Product | HCID 14851257 | HCID 14851257 | 47.7% |
Reaction Steps
2-Bromo-3-(2-methoxyethoxy)-4-ethylsulfonyl benzoic acid (6.1 g, 0.018 mol) was diluted in 50 mL of methylene chloride and 2 drops of DMF were added, followed by the slow addition of oxalyl chloride (3.81 g, 0.03 mol). After the addition was complete, the solution was refluxed for 1 hour, cooled and concentrated under vacuum. The crude acid chloride was diluted in 25 mL of methylene chloride and 2.24 g (0.02 mol) of 1,3-cyclohexanedione was added, followed by an excess of triethylamine (4.0 g). After stirring overnight, the organic layer was washed three times with dilute (1 N) hydrochloric acid, dried and concentrated. The crude enol ester was dissolved in 25 mL of acetonitrile and ten drops of acetone cyanohydrin and 4 mL of triethylamine were added and this reaction mixture was stirred at room temperature for 48 hours. The organic phase was washed three times with 1 N hydrochloric acid and then extracted with base. The base extracts were combined and acidified and extracted three times with 50 mL of methylene chloride. The methylene chloride extracts were dried, concentrated and chromatographed on silica gel using ether/methylene chloride/acetic acid to give 3.96 g of pure 2-[2'-bromo-3'-(2-methoxyethoxy)-4'-ethylsulfonylbenzoyl]-1,3-cyclohexanedione.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US04957538 |
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| Source dataset | uspto-grants-1990_09 |
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| ORD ID | ord-000d1e9abaab4e92a387099538e6146f |
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| Source note | uspto-grants-1990_09 |
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