In 2019,Journal of Organometallic Chemistry included an article by Lahiji, Fatemeh Khadem; Ariafard, Alireza. Category: piperidines. The article was titled 《Revisiting the mechanism of acetylenic amine N-Oxide rearrangement catalyzed by Gold(I) complexes from a DFT perspective》. The information in the text is summarized as follows:
In this study, we used d. functional theory (DFT) to reinvestigate the mechanism proposed by Houk and Zhang et al. (J. Am. Chem. Soc. 2012, 134, 1078) for piperidinone formation through rearrangement of an acetylenic amine N-oxide catalyzed by phosphine gold(I) complexes. For this rearrangement, the C-C coupling was proposed to be the rate-determining step with activation energy as high as 35.8 kcal/mol. Such a barrier seems inconsistent with the fact that the actual reaction proceeds under very mild conditions (0 °C, 1 h, in CH2Cl2). In the original report, it was proposed that the C-C coupling takes place via a mechanism which we called “”front-side addition””. Interestingly, we found that the C-C coupling step becomes energetically more favorable if it occurs via another mechanism called “”back-side addition””. We explored the effect of different phosphine ligands on all conceivable steps of the catalytic reaction and found that while the other steps are not highly sensitive to the phosphine identity, the C-C coupling one shows a considerable degree of dependency; the more electron-donating the phosphine ligand, the lower the rate-limiting step barrier. The experimental process involved the reaction of 1-Methyl-4-piperidone(cas: 1445-73-4Category: piperidines)
1-Methyl-4-piperidone(cas: 1445-73-4) is a member of piperidine. Piperidine-containing compounds are also frequently employed in synthesis as ligands or auxiliaries. Accordingly, many efforts have been devoted to the development of novel methods for the synthesis of these compounds over the years.Category: piperidines
Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem