Ethylene Glycol → 1-[5-(2-Methyl-[1,3]dioxolan-2-yl)-furan-2-ylmethyl]-4-nitro-1H-pyrazole

HRID 2064920Notes

Reaction equation

HRID 2064920 reaction equation
N#N.[N+:3]([C:6]1[CH:7]=[N:8][N:9]([CH2:11][C:12]2[O:16][C:15]([C:17](=[O:19])[CH3:18])=[CH:14][CH:13]=2)[CH:10]=1)([O-:5])=[O:4].[CH2:20](O)[CH2:21][OH:22].CC1C=CC(S(O)(=O)=O)=CC=1>C1(C)C=CC=CC=1.CC(=O)OCC.O>[CH3:18][C:17]1([C:15]2[O:16][C:12]([CH2:11][N:9]3[CH:10]=[C:6]([N+:3]([O-:5])=[O:4])[CH:7]=[N:8]3)=[CH:13][CH:14]=2)[O:22][CH2:21][CH2:20][O:19]1

Participants

8

Reactant 4

HCID 174Ethylene GlycolHCID 947NitrogenHCID 6101p-Toluenesulfonic acidHCID 669282261-[5-(4-Nitro-pyrazol-1-ylmethyl)-furan-2-yl]-ethanone

Product 1

HCID 669285641-[5-(2-Methyl-[1,3]dioxolan-2-yl)-furan-2-ylmethyl]-4-nitro-1H-pyrazole

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 1140TolueneSolventHCID 8857Ethyl AcetateSolvent

Procedure

In a flame dried round-bottomed flask equipped with a magnetic stir bar and a Dean-Stark apparatus under inert atmosphere (N2), a solution of 1-[5-(4-nitro-pyrazol-1-ylmethyl)-furan-2-yl]-ethanone (3.40 g, 14.46 mmol), ethylene glycol (8.1 mL, 144.84 mmol) and TsOH (28 mg, 0.15 mmol) in toluene (150.0 mL) was heated to reflux for 4 h. The reaction mixture was allowed to cool to rt. Water (200 mL) and EA (40 mL) were added and the aq. phase was extracted with EA (2×80 mL). The combined org. extracts were washed with sat. aq. NaHCO3 (200 mL), dried over MgSO4, filtered, and the solvents were removed under reduced pressure. Purification of the residue by FC (60:40 hept-EA) gave the title compound as a yellow oil. TLC: rf (60:40 hept-EA)=0.31. LC-MS-conditions 02: tR=0.91 min. 1H NMR (400 MHz, CDCl3) δ 1.72 (s, 3H), 3.99 (dd, J=4.5, 2.5 Hz, 2H), 4.06 (dd, J=4.4, 2.5 Hz, 2H), 5.31 (s, 2H), 6.35 (d, J=3.3 Hz, 1H), 6.42 (d, J=3.3 Hz, 1H), 8.09 (s, 1H), 8.12 (s, 1H).

Workup

  1. customIn a flame dried round-bottomed flask equipped with a magnetic stir bar
  2. temperatureto reflux for 4 h
  3. extractionthe aq. phase was extracted with EA (2×80 mL)
  4. washextracts were washed with sat. aq. NaHCO3 (200 mL)
  5. dry with materialdried over MgSO4
  6. filtrationfiltered
  7. customthe solvents were removed under reduced pressure
  8. customPurification of the residue by FC (60:40 hept-EA)

Sources & evidence

ORD record
ord-44f2dc82ef9e477cbe6fce0d2819cdf2
Source dataset
uspto-grants-2012_10
Patent number
US08288419B2

Reaction notes

Loading…