tert-Butanol → tert-Butyl (3-Amino-1-phenyl-1H-pyrazol-4-yl)carbamate

HRID 2360546Notes

Reaction equation

HRID 2360546 reaction equation
[N+:1]([C:4]1[C:5](C(O)=O)=[N:6][N:7]([C:9]2[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=2)[CH:8]=1)([O-])=O.C([N:20](CC)CC)C.C1(P(N=[N+]=[N-])(C2C=CC=CC=2)=O)C=CC=CC=1.FC(F)(F)[C:44]([OH:46])=[O:45].[C:49](O)([CH3:52])([CH3:51])[CH3:50]>O1CCOCC1>[NH2:20][C:5]1[C:4]([NH:1][C:44](=[O:45])[O:46][C:49]([CH3:52])([CH3:51])[CH3:50])=[CH:8][N:7]([C:9]2[CH:10]=[CH:11][CH:12]=[CH:13][CH:14]=2)[N:6]=1

Participants

7

Reactant 5

HCID 6386tert-ButanolHCID 6422Trifluoroacetic acidHCID 8471TriethylamineHCID 199401P,P-Diphenylphosphinic azideHCID 230849354-Nitro-1-phenyl-1H-pyrazole-3-carboxylic acid

Product 1

HCID 57717456tert-Butyl (3-Amino-1-phenyl-1H-pyrazol-4-yl)carbamate

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Procedure

A solution of 4-nitro-1-phenyl-1H-pyrazole-3-carboxylic acid (20.0 g, 85.8 mmol), triethylamine (36.0 mL, 257.3 mmol), and diphenylphosphoryl azide (37.8 g, 137.2 mmol) in dioxane (400 mL) and tert-butanol (200 mL) was heated to reflux for 16 hours. The reaction was evaporated to dryness in vacuo, diluted with methylene chloride (400 mL) and treated with trifluoroacetic acid (128 g, 857.7 mmol). The solution was stirred at ambient temperature for 16 hours. The reaction was evaporated in vacuo and the resulting oil diluted with hexanes (750 mL), ethyl acetate (150 mL) and methylene chloride (100 mL). The solids were filtered, washed with above solvent system (hexanes:ethyl acetate:methylene chloride 75:15:10), and dried to give the desired product as yellow solid. 1H NMR (CDCl3) δ 8.43 (s, 1H), 7.62 (m, 2H), 7.48 (m, 2H), 7.37 (m, 1H).

Workup

  1. temperatureto reflux for 16 hours
  2. customThe reaction was evaporated to dryness in vacuo
  3. additiondiluted with methylene chloride (400 mL)
  4. customThe reaction was evaporated in vacuo
  5. additionthe resulting oil diluted with hexanes (750 mL), ethyl acetate (150 mL) and methylene chloride (100 mL)
  6. filtrationThe solids were filtered
  7. washwashed with above solvent system (hexanes:ethyl acetate:methylene chloride 75:15:10)
  8. customdried

Sources & evidence

ORD record
ord-0408a0d56fbf45728fdfb98b6bb303e3
Source dataset
uspto-grants-2014_04
Patent number
US08686020B2

Reaction notes

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