3-Methyl-1,2-cyclopentanedione → 5-(6-{3-[(1H-benzimidazol-2-yl)(1-methylpiperidin-4-yloxy)methyl]-4-fluorophenyl}hex-5-ynylimino)-2-methylcyclopent-1-enol

Participants

Reaction Steps

A mixture of 6-{3-[(1H-benzimidazol-2-yl)(1-methylpiperidin-4-yloxy)methyl]-4-fluorophenyl}hex-5-ynylamine, oxalate (example 557, 50 mg), 3-methyl-1,2-cyclopentanedione (11.8 mg) in ethanol (2 mL) is refluxed for 2 h. The mixture is then cooled, diluted with water and 1N sodium hydroxide and extracted with ethyl acetate. Pooled extracts are dried over magnesium sulfate and concentrated under reduced pressure. The residue is purified by chromatography over silica gel (gradient dichloromethane/methanol/ammonia from 100/0/0.5 to 95/5/0.5) to afford 5-(6-{3-[(1H-benzimidazol-2-yl)(1-methylpiperidin-4-yloxy)methyl]-4-fluorophenyl}hex-5-ynylimino)-2-methylcyclopent-1-enol. TLC (Eluent: CH2Cl2/MeOH/NH4OH 95/5/0.5) Rf=0.30.

Provenance & Evidence