26872-08-2Relevant articles and documents
Synthesis, structure and N-N bonding character of 1,1-disubstituted indazolium hexafluorophosphate
Ning, Yingtang,Kawahata, Masatoshi,Yamaguchi, Kentaro,Otani, Yuko,Ohwada, Tomohiko
supporting information, p. 1881 - 1884 (2018/02/23)
1,1-Disubstituted indazolium hexafluorophosphates were synthesized via intramolecular electrophilic amination reactions under mild conditions. The crystal structures were determined and are consistent with the presence of a stable N-N bond, which can be cleaved by hydrogenation. Both experimental and computational studies suggest a covalent bonding character of the N-N bond, with diminished aromaticity of the newly formed pyrazolium ring due to the quaternary ammonium atom (N1), in contrast to the aromatic character of the parent indazole.
Modified fry cyanation of a chiral pyridinium salt: Asymmetric syntheses of (-)-coniine and (-)-solenopsin A
Vu, Van Ha,Jouanno, Laurie-Anne,Cheignon, Adele,Roisnel, Thierry,Dorcet, Vincent,Sinbandhit, Sourisak,Hurvois, Jean-Pierre
, p. 5464 - 5474 (2013/09/02)
The synthesis of chiral 2-cyano-Δ4-tetrahydropyridine 5 was carried out in 85 % yield through a modified two-step Fry reductive cyanation of pyridinium salt (+)-3c that used lithium triethylborohydride as the hydride donor. An alkylation-reduction sequence provided 2-alkyl-substituted tetrahydropyridines (+)-10a and (+)-10b in 72-75 % yield after chromatographic purification. This protocol has been applied to the asymmetric syntheses of piperidine alkaloids (-)-coniine and (-)-solenopsin A. The two-step reductive cyanation of chiral pyridinium salt (+)-3c afforded α-amino nitrile 5 in 85 % yield, which underwent an alkylation-reduction sequence followed by removal of the chiral moiety to yield the hemlock alkaloid (-)-coniine as its mandelate salt (>99:1 er). This reaction sequence was also used for the synthesis of the trans-2,6-disubstituted piperidine alkaloid (-)-solenopsin A. Copyright
Efficient macrocyclization achieved via conformational control using intermolecular noncovalent π-cation/arene interactions
Bolduc, Philippe,Jacques, Alexandre,Collins, Shawn K.
supporting information; experimental part, p. 12790 - 12791 (2010/11/04)
Quinolinium salt 3 is an effective additive that acts as a conformation control element (CCE) to promote macrocyclization to form rigid cyclophanes via olefin metathesis or Glaser-Hay coupling, which do not cyclize in the absence of the additive. The additives are easily synthesized and highly modifiable and have solubility profiles which allow for simple recovery via filtration.
An ion-pair template for rotaxane formation and its exploitation in an orthogonal interaction anion-switchable molecular shuttle
Barrell, Michael J.,Leigh, David A.,Lusby, Paul J.,Slawin, Alexandra M. Z.
supporting information; experimental part, p. 8036 - 8039 (2009/04/13)
(Chemical Equation Presented) Chloride control: The serendipitous discovery of a molecular recognition motif that is triggered by the formation of an anion-palladium coordination bond is exploited as an efficient rotaxane-forming template and as the basis of a molecular shuttle. The macrocycle of this rotaxane moves between the two stations when the counterion is changed from chloride to hexafluorophosphate (see picture).
