Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Water | HCID 962 | — |
| Reactant | 3-Methyl-1H-indol-4-ol | HCID 589774 | — |
| Reactant | Sodium cyanoborohydride | HCID 5003444 | — |
| Solvent | Acetic Acid | HCID 176 | — |
| Product | HCID 13875439 | HCID 13875439 | 44.4% |
Reaction Steps
1.35 g of sodium cyanoborohydride are gradually added to a solution of 1.0 g of 3-methyl-1H-indol-4-ol in 35 ml of acetic acid under argon cooled to a temperature of about 15° C. The reaction mixture is allowed to warm up to ambient temperature. After 16.5 hours, the reaction mixture is treated with 15 ml of water, and then concentrated to dryness under reduced pressure. The residue is taken up in 75 ml of ethyl acetate, and then treated with 60 ml of a saturated sodium hydrogen carbonate solution. After stirring for 1 hour and then settling out, the organic phase is separated and the aqueous phase is extracted with 50 ml of ethyl acetate. The organic phases are combined, washed with saturated brine, dried over anhydrous magnesium sulfate, filtered, and then concentrated to dryness under reduced pressure. The residue is purified by chromatography on a 70 g cartridge of 15-40 μm silica, elution being carried out with an 80/20 v/v cyclohexane/ethyl acetate mixture, with a flow rate of 80 ml/min. 0.45 g of 4-hydroxy-3-methylindoline is thus obtained in the form of a pale yellow solid, the characteristics of which are the following:
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US09133168B2 |
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| Source dataset | uspto-grants-2015_09 |
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| ORD ID | ord-55ab8fdb06d849dfa81946d22ed7c450 |
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| Source note | uspto-grants-2015_09 |
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