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[摘要]：The reaction of aldehydes (pentanal, benzaldehyde, 4-methoxybenzaldehyde, 4-nitrobenzaldehyde, salicylaldehyde, pyridin-2-carbaldehyde) with 1-aminocyclopentancarboxamide or (S)-2-amino-2,3-dimethylbutanamide has been used to prepare substituted imidazolidin-4-ones 1a-g (a: R-1 = CH3(CH2)(3); b: R-1 = C6H5; c: R-1 = 4-CH3OC6H4; d: R-1 = 4-NO2C6H4; e: R-1 = 2-HOC6H4; f: R-1 = 2-pyridyl; for R-2 = R-3 = (CH2)(4)), and g: R-1 = 2-pyridyl; for R-2 = CH3; R-3 = CH(CH3)(2)) in the yields of 53-83%. Subsequent oxidations with various reagents gave the corresponding 4,5-dihydro-1H-imidazol-5-ones 2a-g: Pd/C (72-93%), DDQ (25-80%), and MnO2 (30-77%). Structure of the prepared compounds 1a-g and 2a-g was verified by H-1 NMR and C-13 NMR spectroscopy, EI-MS and elemental analysis. X-ray diffraction was performed in the case of compounds 1e and 2e. |
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