Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Methyl Acrylate | HCID 7294 | — |
| Reactant | Triethylamine | HCID 8471 | — |
| Reactant | tert-Butyl 3-iodo-5-nitro-1H-indazole-1-carboxylate | HCID 46835639 | — |
| Catalyst | Tetrabutylammonium Iodide | HCID 67553 | — |
| Solvent | Water | HCID 962 | — |
| Solvent | Dimethylformamide | HCID 6228 | — |
| Product | HCID 67530624 | HCID 67530624 | 37% |
Reaction Steps
A solution of tert-butyl 3-iodo-5-nitro-1H-indazole-1-carboxylate (Intermediate 44, 4.6 g; 11.8 mmol) in DMF (76 ml) and water (12 ml) was treated with triethylamine (12 ml; 86 mmol), methyl acrylate (10.4 ml; 115 mmol) and tetrabutyl ammonium iodide (8.6 g; 23 mmol). The mixture was degassed and then dichlorobis(triphenylphosphine)palladium (II), (1.68 g; 2.4 mmol) was added. The mixture was heated to 50° C. for 18 hours and the volatile solvent removed in vacuo. The mixture was poured into water (600 ml) and extracted with EtOAc. The combined organic extracts were washed with water, dried over sodium sulfate, filtered and the solvent removed in vacuo. The residue was purified by column chromatography (silica) eluting with petroleum ether containing increasing amounts of EtOAc to give tert-butyl 3-(3-methoxy-3-oxoprop-1-enyl)-5-nitro-1H-indazole-1-carboxylate as a light brown solid (1.5 g, 37%). A solution of this residue (200 mg; 0.58 mmol) in methanol (100 ml) was treated with palladium (100mg, 5% on C). The mixture was stirred under hydrogen for 18 hours, filtered and the solvent removed in vacuo. The residue was purified by column chromatography (silica) eluting with petroleum ether containing increasing amounts of EtOAc to give the title compound as an off-white solid.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US09150519B2 |
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| Source dataset | uspto-grants-2015_10 |
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| ORD ID | ord-c48cdab11f5841c5850925da24e5181e |
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| Source note | uspto-grants-2015_10 |
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