Acetic Anhydride → tert-butyl 3-[2-(acetyloxy)ethoxy]-5-amino-1-methyl-1H-pyrazole-4-carboxylate

HRID 1368640Notes

Reaction equation

HRID 1368640 reaction equation
[NH2:1][C:2]1[N:6]([CH3:7])[N:5]=[C:4]([O:8][CH2:9][CH2:10][OH:11])[C:3]=1[C:12]([O:14][C:15]([CH3:18])([CH3:17])[CH3:16])=[O:13].C(N(CC)CC)C.[C:26](OC(=O)C)(=[O:28])[CH3:27]>O1CCCC1.CN(C)C1C=CN=CC=1>[C:26]([O:11][CH2:10][CH2:9][O:8][C:4]1[C:3]([C:12]([O:14][C:15]([CH3:18])([CH3:17])[CH3:16])=[O:13])=[C:2]([NH2:1])[N:6]([CH3:7])[N:5]=1)(=[O:28])[CH3:27]

Participants

6

Reactant 3

HCID 7918Acetic AnhydrideHCID 8471TriethylamineHCID 22281924tert-butyl 5-amino-3-(2-hydroxyethoxy)-1-methyl-1H-pyrazole-4-carboxylate

Product 1

HCID 22281904tert-butyl 3-[2-(acetyloxy)ethoxy]-5-amino-1-methyl-1H-pyrazole-4-carboxylate

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 8028TetrahydrofuranSolvent

Procedure

To tert-butyl 5-amino-3-(2-hydroxyethoxy)-1-methyl-1H-pyrazole-4-carboxylate (Preparation 11) (60 g) in tetrahydrofuran (500 ml), under nitrogen and at room temperature, was added triethylamine (41.7 ml), 4-dimethylaminopyridine (400 mg) followed by acetic anhydride (28.6 ml) dropwise. The reaction was stirred at room temperature overnight and was then concentrated under reduced pressure. The residue was diluted with ethyl acetate (300 ml) and washed with brine (2×100 ml). The organics were dried with magnesium sulfate, filtered and concentrated under reduced pressure to yield the desired product as white solid (71 g).

Workup

  1. concentrationwas then concentrated under reduced pressure
  2. additionThe residue was diluted with ethyl acetate (300 ml)
  3. washwashed with brine (2×100 ml)
  4. dry with materialThe organics were dried with magnesium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-e60e33079e44433cac9dbcfc6030c20a
Source dataset
uspto-grants-2003_06
Patent number
US06573270B1

Reaction notes

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