Abstract
The reductive amination of appropriate ketopyrrolidines leading to 3,5-dialkylindolizidines usually gives stereoselectively the indolizidine with a cis relative stereochemistry on the piperidine moiety. We report herein unexpected results concerning the effect of the nature of the C3 subsiituent on this stereoselectivity.
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References and notes
Tokuyama, T.; Nishimori, N.; Karle, I. L.; Edwards, M. W.; Daly J. W. Tetrahedron 1986, 42, 3453.
Michael, J. P. Natural Products Reports 1990, 485.
Fleurant, A.; Célérier, J. P.; Lhommet, G. Tetrahedron: Asymmetry 1993, 4, 1429.
Machinaga, N.; Kibayashi, C. J. Org. Chem. 1992, 57, 5178. Momose, T; Toyooka, N.; Seki, S.; Hirai, Y. Chem. Pharm. Bull. 1990, 38, 2072.
Célimène, C.; Dhimane, H.; LeBail, M.; Lhommet, G. Tetrahedron Lett. 1994, 35,6105.Trans and cis isomers of 1 were not separable by chromatography.
Reduction of 1 was carried out by using NaBH4/CaCl2 system in THE/EtOH (1/1). At this stage the pure trans alcohol 2 was isolated in 67% yield. Acetate 3 was prepared from 2 using acetyl chloride in pyridine (92% yield).
Epimers 6 were isolated by column chromatography (Si02, Et20/Pentane, 3/1).
The key intermediate 1 could not be separated from its cis isomer (4%) and therefore 5 was used as a trans/cis (96/4) mixture.
Product 7b was purified by column chromatography (Si02, Et20/Pentane, 3/1)
The two others stereomers were present in too low concentration to be isolated.
The ester moiety reduction was performed at -78°C using LiAIH4 in THF.
This acetate was obtained by refluxing 9 in THF in the presence of Ac20 (1.1 equiv.) and Et3N (4 equiv.). Otherwise Ac20/Pyridine or Ac20/DCC/DMAP left 9 unchanged. The use of AcCI instead of Ac20 gave a complex mixture.
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© 1998 Springer Japan
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Bacque-Vanucci, C., Celimene, C., David, M., Dhimane, H., Lhommet, G. (1998). Anodic Oxydation of Heterocycles: Alkaloids Synthesis. In: Torii, S. (eds) Novel Trends in Electroorganic Synthesis. Springer, Tokyo. https://doi.org/10.1007/978-4-431-65924-2_17
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DOI: https://doi.org/10.1007/978-4-431-65924-2_17
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