Potassium Carbonate → 1-(4-methyl-2-nitro-1H-imidazol-1-yl)-3-methyl-2-butene

HRID 2293898Notes

Reaction equation

HRID 2293898 reaction equation
[CH3:1][C:2]([CH3:6])=[CH:3][CH2:4]Br.C([O-])([O-])=O.[K+].[K+].[CH3:13][C:14]1[N:15]=[C:16]([N+:19]([O-:21])=[O:20])[NH:17][CH:18]=1>CC(C)=O>[CH3:13][C:14]1[N:15]=[C:16]([N+:19]([O-:21])=[O:20])[N:17]([CH2:4][CH:3]=[C:2]([CH3:6])[CH3:1])[CH:18]=1

Participants

5

Reactant 3

HCID 11430Potassium CarbonateHCID 700922-Butene, 1-bromo-3-methyl-HCID 178430893HCID 178430893, compound

Product 1

HCID 151860141-(4-methyl-2-nitro-1H-imidazol-1-yl)-3-methyl-2-butene

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

3,3-Dimethylallyl bromide (14.08 g, 94.49 mmol) was added to a suspension of anhydrous K2CO3 (13.0 g, 94.20 mmol) and 4-methyl-2-nitroimidazole (10.0 g, 78.74 mmol, D. P. Davies et al, J. Heterocyclic Chem., 1982, 19, 253-256) in dry acetone (100 mL). The reaction mixture was stirred at room temperature under nitrogen atmosphere for 15 hours. The insoluble inorganic material was removed by filtration and the filtrate was evaporated to afford a brown paste which was loaded onto a silica gel column and eluted with hexane ethyl acetate (8.5:1.5). The fractions containing the compound with Rf 0.51 (silica gel TLC, hexane-ethyl acetate, 7:3) were collected and evaporated to afford a solid which was recrystallized from ethyl acetate-hexane to provide 1-(4-methyl-2-nitro-1H-imidazol-1-yl)-3-methyl-2-butene as a light yellow crystalline solid in 60% (9.21 g) yield; mp. 53°--54° C; 1H NMR (CDCl3) δ 1.80 [s, 6H, C(CH3)2 ], 2.26 (s, 3H, imi-CH3), 4.97 (d, 2H, J=7.26 Hz, NCH2), 5.36 (t, 1H, J=7.26 Hz, CH2CH) and 6.90 (s, 1H, imi-CH). 13C NMR (CDCl3) δ 13.80 (imi-CH3), 18.16 & 25.70 [C(CH3)2 ], 47.76 (NCH2), 117.35 (CH2CH), 122.77 (imi-CH), 138.09 [C(CH3)2 ], 139.97 (imi-CCH3) and 143.53 (CNO2). MS m/e 196 (M+H)+.

Workup

  1. customThe insoluble inorganic material was removed by filtration
  2. customthe filtrate was evaporated
  3. customto afford a brown paste which
  4. washeluted with hexane ethyl acetate (8.5:1.5)
  5. additionThe fractions containing the compound with Rf 0.51 (silica gel TLC, hexane-ethyl acetate, 7:3)
  6. customwere collected
  7. customevaporated
  8. customto afford a solid which
  9. customwas recrystallized from ethyl acetate-hexane

Sources & evidence

ORD record
ord-80c87bd6374145479fd6e4d664df8fc2
Source dataset
uspto-grants-1997_11
Patent number
US05688487

Reaction notes

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