3,4-Dichlorobenzaldehyde → HCID 68828353, compound

HRID 1786143Notes

Reaction equation

HRID 1786143 reaction equation
[N:1]1([S:6]([CH2:9][C:10](=[O:12])[CH3:11])(=[O:8])=[O:7])[CH2:5][CH2:4][CH2:3][CH2:2]1.[Cl:13][C:14]1[CH:15]=[C:16]([CH:19]=[CH:20][C:21]=1[Cl:22])[CH:17]=O>C1COCC1.CC(C)[O-].CC(C)[O-].CC(C)[O-].CC(C)[O-].[Ti+4]>[Cl:13][C:14]1[CH:15]=[C:16]([CH:17]=[C:9]([S:6]([N:1]2[CH2:2][CH2:3][CH2:4][CH2:5]2)(=[O:7])=[O:8])[C:10](=[O:12])[CH3:11])[CH:19]=[CH:20][C:21]=1[Cl:22]

Participants

5

Reactant 2

HCID 227103,4-DichlorobenzaldehydeHCID 57597021HCID 57597021, compound

Product 1

HCID 68828353HCID 68828353, compound

Reagents, catalysts & solvents 2

HCID 11026Titanium isopropoxideCatalystHCID 8028TetrahydrofuranSolvent

Conditions

Temperature
80 °C

Procedure

Alternatively, the Bignelli reaction was carried out in two steps with higher yields. To 1-(pyrrolidin-1-ylsulfonyl)propan-2-one in THF was added an equivalent amount of 3,4-dichlorobenzaldehyde and a catalytic amount of titanium tetraisopropoxide. The reaction was stirred at 80° C. overnight. Solvent was removed and the residue was purified by silica flash chromatography (0% to 15% ethyl acetate-hexanes) to provide 4-(3,4-dichlorophenyl)-3-(pyrrolidin-1-ylsulfonyl)but-3-en-2-one. The product obtained was dissolved in 1,4-dioxane and one equivalent of 3-methyl-1H-pyrazol-5-amine was added. The reaction was stirred at 80° C. for 24-48 hrs. Solvent was removed and product was obtained after flash chromatography (silica gel, 0% to 40% ethyl acetate-hexanes).

Workup

  1. customAlternatively, the Bignelli reaction
  2. customwith higher yields
  3. customSolvent was removed
  4. customthe residue was purified by silica flash chromatography (0% to 15% ethyl acetate-hexanes)

Sources & evidence

ORD record
ord-9c2886ef1d6d4ad683a8640399023baa
Source dataset
uspto-grants-2009_03
Patent number
US07507730B2

Reaction notes

Loading…