Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Triethylsilane | HCID 12052 | — |
| Reactant | Trifluoromethanesulfonic acid | HCID 62406 | — |
| Reactant | Sodium Bicarbonate | HCID 516892 | — |
| Reactant | HCID 19780688 | HCID 19780688 | — |
| Solvent | Dichloromethane | HCID 6344 | — |
| Product | HCID 12508514 | HCID 12508514 | — |
Reaction Steps
Trifluoromethanesulphonic acid (0.2 ml, 2.3 mM) in dichloromethane (0.5 ml) was added dropwise to a solution of the epsilon-lactone of 3-(2-hydroxy-4,6-dimethylbenzoyl)propionic acid, [m.p. 77° C.; prepared by the method described in Acta. Chem. Scand. 1972, 26, 2372, but starting from 3-(2-hydroxy-4,6-dimethylbenzoyl)propionic acid, itself prepared as described in Liebigs Ann. Chem. 1985, 560] in dichloromethane (1 ml) at 0° C. under argon, followed by a solution of triethylsilane (200 mg, 1.7 mM) in dichloromethane (0.5 ml). After 5 minutes, a further portion of trifluoromethanesulphonic acid (0.2 ml, 2.3 mM) in dichloromethane (0.5 ml) was added followed by triethylsilane (200 mg; 1.7 mM) in dichloromethane (0.5 ml). The reaction mixture was stirred for 2 hours at ambient temperature, then poured into saturated sodium hydrogen carbonate solution and extracted with dichloromethane. The combined extracts were washed with brine, dried (Na2SO4), and the solvent was removed by evaporation. The residual oil was purified by flash chromatography, eluting with hexane/dichloromethane (1:1 v/v increasing in polarity to 1:3 v/v), giving the epsilon-lactone of 4-(2-hydroxy-4,6-dimethylphenyl)butyric acid (C) as a colourless oil; NMR: 2.10(2H,tt), 2.29(6H,s), 2.43(2H,t), 2.79(2H,t), 6.75(1H,s), 6.86(1H,s); I.R (thin film) 1720 cm-1.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US05185452 |
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| Source dataset | uspto-grants-1993_02 |
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| ORD ID | ord-1e1f5505f61740d1a78309d523b16467 |
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| Source note | uspto-grants-1993_02 |
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