Novel syntheses of hexahydro-1H-pyrrolo[1,2-a]ĭmidazoles and Octahydroimidazo[1,2-a]pyridines.
1-Phenyl-5-(benzotriazol-1-yl)hexahydro-1H-pyrrolo[1,2-a]ĭmidazole (18) and 1-phenyl-5-benzotriazolyloctahydroimidazo[1,2-a]pyridine (27) were readily prepared from succindialdehyde or glutaraldehyde, benzotriazole, and N-phenylethylenediamine. Synthons 18 and 27 reacted with Grignard reagents, allylsilanes, silyl ethers, and triethyl phosphite to produce 1-phenyl-5-substituted-hexahydro-1H-pyrrolo[1,2-a]ĭmidazoles 20a-f, 22, 24a,b, and 25 and 1-phenyl-5-substituted-octahydroimidazo[1, 2-a]pyridines 28a-e, 32, 33a,b, and 34 in good to excellent yields. The configurations of 20, 22, 24, and 25 were determined to be cis isomers by NOE experiment, while the configurations and conformations of 28a-e, 32, 33a,b, and 34 were elucidated by (1)H-(1)H COSY and (1)H-(13)C COSY.
Katritzky
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Center for Heterocyclic Chemistry, Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, USA.
Qiu
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He
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Yang
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B
D007093:Imidazoles / Q000138:chemical synthesis* / Q000737:chemistry; D007202:Indicators and Reagents; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry; D011758:Pyrroles / Q000138:chemical synthesis* / Q000737:chemistry
D007093:Imidazoles; D007202:Indicators and Reagents; D011725:Pyridines; D011758:Pyrroles