Diisopropylethylamine → tert-butyl 3-(1-methyl-4-nitro-1H-pyrazol-5-ylamino)propylcarbamate

HRID 1185265Notes

Reaction equation

HRID 1185265 reaction equation
Cl[C:2]1[N:6]([CH3:7])[N:5]=[CH:4][C:3]=1[N+:8]([O-:10])=[O:9].[NH2:11][CH2:12][CH2:13][CH2:14][NH:15][C:16](=[O:22])[O:17][C:18]([CH3:21])([CH3:20])[CH3:19].CCN(C(C)C)C(C)C>CCO>[CH3:7][N:6]1[C:2]([NH:11][CH2:12][CH2:13][CH2:14][NH:15][C:16](=[O:22])[O:17][C:18]([CH3:20])([CH3:19])[CH3:21])=[C:3]([N+:8]([O-:10])=[O:9])[CH:4]=[N:5]1

Participants

5

Reactant 3

HCID 81531DiisopropylethylamineHCID 2735700tert-Butyl (3-aminopropyl)carbamateHCID 123448365-chloro-1-methyl-4-nitro-1H-pyrazole

Product 1

HCID 67436676tert-butyl 3-(1-methyl-4-nitro-1H-pyrazol-5-ylamino)propylcarbamateYield 86.9%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Conditions

Temperature
130 °C

Procedure

A mixture of 5-chloro-1-methyl-4-nitro-1H-pyrazole (0.81 g, 5 mmol), tert-butyl 3-aminopropylcarbamate (0.85 g, 4.88 mmol) and DIPEA (1.8 mL, 10.5 mmol) in EtOH (5 mL) was heated at 130° C. in the microwave for 90 min. On cooling the reaction mixture was concentrated under reduced pressure and the residue purified via silica gel column chromatography (0-100% EtOAc/isohexane) to afford tert-butyl 3-(1-methyl-4-nitro-1H-pyrazol-5-ylamino)propylcarbamate as a yellow gum (1.27 g, 85%). A mixture of this gum (0.3 g, 1 mmol), K2CO3 (0.41 g, 3 mmol) and methyl iodide (0.1 mL, 1.58 mmol) in DMF (5 mL) was stirred at 60° C. for 18 hr. More methyl iodide (0.1 mL, 1.58 mmol) was added and stirring at 60° C. was continued for 24 hr. The reaction mixture was cooled and concentrated under reduced pressure. The residue was triturated in DCM (100 mL), filtered and the filtrate concentrated under reduced pressure. Purification via silica gel column chromatography (0-100% EtOAc/isohexane) gave tert-butyl 3-(methyl(1-methyl-4-nitro-1H-pyrazol-5-yl)amino)propylcarbamate as a pale yellow gum (0.122 g, 38%). 1H-NMR (400 MHz, CDCl3) δ 8.03 (s, 1H), 4.60 (s, 1H), 3.77 (s, 3H), 3.20-3.14 (m, 4H), 2.86 (s, 3H), 1.72-1.61 (m, 2H), 1.42 (s, 9H).

Workup

  1. temperatureOn cooling the reaction mixture
  2. concentrationwas concentrated under reduced pressure
  3. customthe residue purified via silica gel column chromatography (0-100% EtOAc/isohexane)

Sources & evidence

ORD record
ord-0a15a5ef9d5547a394d5950baf4f555d
Source dataset
uspto-grants-2014_03
Patent number
US08669361B2

Reaction notes

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