Acetic Anhydride → HCID 20277273, compound

HRID 894726Notes

Reaction equation

HRID 894726 reaction equation
[C:1]([C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][C:4]=1[CH:9]1[C:14]([C:15]([O:17][CH3:18])=[O:16])=[C:13]([CH:19]=O)[NH:12][C:11]([CH3:21])=[C:10]1[C:22]([OH:24])=[O:23])#[N:2].Cl.[NH2:26]O.C([O-])(=O)C.[Na+].C(OC(=O)C)(=O)C>C(O)(=O)C.C(OCC)C>[C:19]([C:13]1[NH:12][C:11]([CH3:21])=[C:10]([C:22]([OH:24])=[O:23])[CH:9]([C:4]2[CH:5]=[CH:6][CH:7]=[CH:8][C:3]=2[C:1]#[N:2])[C:14]=1[C:15]([O:17][CH3:18])=[O:16])#[N:26]

Participants

7

Reactant 4

HCID 7918Acetic AnhydrideHCID 443297Hydroxyamine hydrochlorideHCID 517045Sodium AcetateHCID 20277282HCID 20277282, compound

Product 1

HCID 20277273HCID 20277273, compoundYield 51.5%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 3283Diethyl EtherSolvent

Procedure

To a solution of isopropyl ester of 4-(2-cyanophenyl)-6-formyl-5-methoxycarbonyl-2-methyl-1,4-dihydropyridine-3-carboxylic acid (3.90 g) in acetic acid (20 ml) were added hydroxylamine hydrochloride (0.88 g) and sodium acetate (1.30 g), and the mixture was stirred for an hour at ambient temperature. To the reaction mixture was added acetic anhydride (3.97 g) with stirring, and the stirring was continued for an hour at ambient temperature and for additional 4 hours at 95°~100° C. After the reaction mixture was allowed to stand at ambient temperature, the acetic acid was removed by distillation under reduced pressure. The resultant residue was diluted with water, neutralized with an aqueous solution of sodium bicarbonate and then extracted twice with ethyl acetate. After the combined extract was washed twice with water and dried, the solvent was removed by distillation under reduced pressure to give an oil, which was allowed to stand overnight and pulverized with a small amount of ethyl ether. The powder was washed with isopropyl ether and recrystallized from methanol to give yellowish-orange crystals of isopropyl ester of 6-cyano-4-(2-cyanophenyl)-5-methoxycarbonyl-2-methyl-1,4-dihydropyridine-3-carboxylic acid (1.99 g), mp 198°~200° C.

Workup

  1. stirringwith stirring
  2. customto stand at ambient temperature
  3. customthe acetic acid was removed by distillation under reduced pressure
  4. additionThe resultant residue was diluted with water
  5. extractionextracted twice with ethyl acetate
  6. extractionAfter the combined extract
  7. washwas washed twice with water
  8. customdried
  9. customthe solvent was removed by distillation under reduced pressure
  10. customto give an oil, which
  11. waitto stand overnight
  12. washThe powder was washed with isopropyl ether
  13. customrecrystallized from methanol

Sources & evidence

ORD record
ord-fbf37ba5d940490dace452a04e41eba5
Source dataset
uspto-grants-1981_08
Patent number
US04284634

Reaction notes

Loading…