反应详情

A stirred solution of 2.0 grams (0.009 mole) of phenyl N-(4-pyridazinyl)carbamate and 1.0 ml (0.010 mole) of cyclopentylamine in tetrahydrofuran is heated under reflux for 18 hours. The reaction mixture is filtered and the filtrate concentrated under reduced pressure to a residue. The residue is purified by column chromatography on silica gel. Elution is accomplished with 10% methanol in methylene chloride. The appropriate fractions are combined and concentrated under reduced pressure to yield 0.2 gram of N-(4-pyridazinyl)-N'-cyclopentylurea. This material is combined with the identical product from a previous reaction to yield 0.5 gram; m.p. 192°-195° C., dec. The nmr spectrum is consistent with the proposed structure. The reaction is repeated several times.

1. temperatureunder reflux for 18 hours
2. filtrationThe reaction mixture is filtered
3. concentrationthe filtrate concentrated under reduced pressure to a residue
4. customThe residue is purified by column chromatography on silica gel
5. washElution
6. concentrationconcentrated under reduced pressure