Preparation of 1-substituted-5-[(2-oxo-2-phenyl)ethyl]imidazoles

New high yield preparation methods were developed for the pharmaceutically interesting compounds, 1-benzyl-, 1-methyl-, and 1H-5-[(2-oxo-2-phenyl)ethyl]imidazoles 1a-c, respectively. The title compounds were synthesized by four different methods using various starting materials. Two of the methods involved transformation reactions of the key intermediates, 1-substituted-5-[(2-nitro-2-phenyl)ethenyl]imidazoles 2a-c and 1-substituted-5-[(2-nitro-2-phenyl)ethyl]imidazoles 3a-c, while the other two utilized the oxidation of 1-substituted-5-[(2-hydroxy-2-phenyl)ethyl]imidazoles 4a-c, with chromic oxide, and the umpolung reaction of benzaldehyde followed by a condensation reaction of the umpolung intermediate with imidazolecarboxaldehydes 6a-c.

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