Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Sulfuric Acid | HCID 1118 | — |
| Reactant | HCID 59562589 | HCID 59562589 | — |
| Reactant | HCID 59562610 | HCID 59562610 | — |
| Solvent | Dichloromethane | HCID 6344 | — |
| Product | HCID 68730923 | HCID 68730923 | — |
Reaction Steps
To an ice cold solution of a mixture of 2-(4-bromo-2-ethylphenyl)-6-methoxymethyl-4,4,6-trimethyl-1,5-dioxaspiro[2.4]heptan-7-one and 2-(4-bromo-2-ethylphenyl)-4-methoxymethyl-4,6,6-trimethyl-1,5-dioxaspiro[2.4]heptan-7-one (5 g, 0.013 mol) in dichloromethane (2.5 ml) is added concentrated sulphuric acid (15 ml), dropwise over 50-60 minutes, maintaining the temperature of the reaction mixture at 5-10° C. The reaction mixture is maintained at 5-10° C. for 10-15 minutes, quenched into crushed ice (75 g) and extracted with dichloromethane (3×50 ml). The organic phases are combined, washed with water, and dried over anhydrous sodium sulfate. The mixture is filtered, and the filtrate is evaporated under reduced pressure. The residue is purified by column chromatography on silica gel to give 4-(4-bromo-2-ethylphenyl)-2-methoxymethyl-2,6,6-trimethylpyran-3,5-dione (1.82 g) as a white solid.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US08895761B2 |
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| Source dataset | uspto-grants-2014_11 |
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| ORD ID | ord-e992aa75d31e412495d03dc13559f0be |
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| Source note | uspto-grants-2014_11 |
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