Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Malonic Acid | HCID 867 | — |
| Reactant | Sulfuric Acid | HCID 1118 | — |
| Reactant | 1-Methyl-4-nitro-1H-pyrrole-2-carbaldehyde | HCID 12345441 | — |
| Catalyst | Piperidine | HCID 8082 | — |
| Solvent | Pyridine | HCID 1049 | — |
| Product | HCID 10679395 | HCID 10679395 | 92% |
Reaction Steps
Alternatively, a mixture of 1-methyl-4-nitro-2-pyrrolecarboxaldehyde (0.20 g, 1.30 mmol), malonic acid (0.68 g, 6.5 mmol), piperidine (2 drops), and pyridine (2 mL) was stirred at room temperature at for 20 h and at 100° C. for 4 h, then 30% aqueous H2SO4 (10 mL) was added. The precipitate that formed was removed by filtration and washed with water to give (E)-1-methyl-4-nitro-2-pyrroleacrylic acid as fine yellow needles (0.23 g, 92%). 1H NMR [(CD3)2SO] δ 12.35 (br s, 1 H, CO2H), 8.13 (d, J=1.9 Hz, 1 H, H-5), 7.44 (d, J=15.9 Hz, 1 H, H-β), 7.41 (d, J=1.9 Hz, 1 H, H-3), 6.46 (d, J=15.9 Hz, 1 H, H-α), 3.79 (s, 3 H, NCH3); 13C NMR δ 167.4 (CO2H), 135.3, 129.9 (C-2,4), 130.6, 127.0, 118.6, 105.8 (C-3,5,α,β), 34.8 (NCH3).
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US06130237 |
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| Source dataset | uspto-grants-2000_10 |
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| ORD ID | ord-8c76a5b394b047729864e279fd807d1d |
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| Source note | uspto-grants-2000_10 |
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