HuagongsheHuagongshe Chemistry Print Report · For research reference only
Acetone → (4R)-5-(Methoxycarbonyl)-2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3-carboxylic acid
Participants
| Role | Name | HCID | Charge |
|---|---|---|---|
| Reactant | Acetone | HCID 180 | — |
| Reactant | Hydrochloric Acid | HCID 313 | — |
| Reactant | (R)-1-(2-methoxyethoxy)methyl-2,6-dimethyl-3-carbomethoxy-4-(3-nitrophenyl)-5-carboxy-1,4-dihydropyridine | HCID 14208796 | — |
| Solvent | Water | HCID 962 | — |
| Solvent | Dichloromethane | HCID 6344 | — |
| Solvent | Tetrahydrofuran | HCID 8028 | — |
| Product | (4R)-5-(Methoxycarbonyl)-2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3-carboxylic acid | HCID 748472 | — |
Reaction Steps
The resolved mono-ester of formula 18 is then deprotected by acid hydrolysis using a dilute (about 1N to about 2N) mineral acid in a suitable water-miscible solvent (preferably acetone or THF) at a temperature between about 0° and about 15° C. for about 30 to about 120 minutes. For example, (R)-1-(2-methoxyethoxy)methyl-2,6-dimethyl-3-carbomethoxy-4-(3-nitrophenyl)-5-carboxy-1,4-dihydropyridine is dissolved in CH2Cl2, treated with 1N HCl at 0° C., and allowed to stand for one hour at room temperature. Then, water (100 mL) is added, and the resulting precipitate is filtered to yield (R)-2,6-dimethyl-3-carbomethoxy-4-(3-nitrophenyl)-5-carboxy-1,4-dihydropyridine (19). (Scheme VI, Step 5)
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
|---|---|
| Patent number | US04761420 |
| Source dataset | uspto-grants-1988_08 |
| ORD ID | ord-f25c5e2824a8409298d1965c750e1b02 |
| Source note | uspto-grants-1988_08 |