643-20-9Relevant articles and documents
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Schweizer,Light
, p. 2963 (1964)
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Synthesis of indolizidine, pyrrolizidine and quinolizidine ring systems by proline-catalyzed sequential α-amination and HWE olefination of an aldehyde
Kauloorkar, Shruti Vandana,Jha, Vishwajeet,Kumar, Pradeep
, p. 18288 - 18291 (2013/10/21)
A general procedure for the synthesis of azabicyclic ring systems viz. indolizidine, pyrrolizidine and quinolizidine has been developed utilizing proline-catalyzed sequential α-amination and Horner-Wadsworth-Emmons (HWE) olefination of an aldehyde as the key step. This method can be further extended to the synthesis of various biologically active natural products containing azabicyclic ring systems.
Hydrogenation of pyrrolizin-3-ones; New routes to pyrrolizidines
Despinoy, Xavier L. M.,McNab, Hamish
experimental part, p. 4502 - 4511 (2009/12/25)
Pyrrolizin-3-ones (e.g.1) can be easily hydrogenated to their hexahydro (pyrrolizidin-3-one) derivatives in the presence of heterogeneous catalysts. Good diastereoselectivity (up to >97:3, depending on catalysts and solvent) can be achieved if the pyrroli
Stereochemistry of β-deuterium isotope effects on amine basicity
Perrin, Charles L.,Ohta, Brian K.,Kuperman, Joshua,Liberman, Jordan,Erdelyi, Mate
, p. 9641 - 9647 (2007/10/03)
Secondary β-deuterium isotope effects on amine basicities are measured using a remarkably precise NMR titration method. Deuteration is found to increase the basicity of methylamine, dimethylamine, benzylamine, N,N-dimethylaniline, 2-methyl-2-azanorbornane, and pyrrolizidine. The increase in dimethylamine arises entirely from enthalpy, contrary to a previous report. The method permits a determination of intramolecular isotope effects in 1-benzyl-4-methylpiperidine and 2-benzyl-2-azanorbornane. It is found that deuteration has a larger isotope effect when either antiperiplanar or synperiplanar to a lone pair, but the synperiplanar effect is smaller, as confirmed by computations. The isotope effect is attributed to a lowered zero-point energy of a C-H bond adjacent to an amine nitrogen, arising from delocalization of either a syn or an anti lone pair, and with no detectable angle-independent inductive effect.