2.B.57.  The Heavy Pnictogenium Cation-Anion Carrier (HPC-AC) Family

Work on the complexation of fluoride anions using group 15 Lewis acids has led to the investigation of the use of these main group compounds as anion transporters. Pnictogen-, calcogen- and halogen-bonded compounds were compared (Plajer et al. 2020). Park et al. 2019 reported on the anion transport properties of tetraarylstibonium and tetraarylbismuthonium cations of the general formula [Ph3PnAr]+ with Pn = Sb or Bi and with Ar = phenyl, naphthyl, anthryl, or pyrenyl. Using EYPC-based large unilamellar vesicles, they showed that these main group cations transport hydroxide, fluoride and chloride anions across phospholipid bilayers. A comparison of the properties of [Ph3SbAnt]+ and [Ph3BiAnt]+ (Ant = 9-anthryl) illustrated the favorable role played by the Lewis acidity of the central pnictogen element with respect to the anion transport. They found that [Ph3SbAnt]+ accelerates the fluoride-induced hemolysis of human red blood cells, an effect that was attributed to the transporter-facilitated influx of toxic fluoride anions (Park et al. 2019).


 

References:

Park, G., D.J. Brock, J.P. Pellois, and F.P. Gabbaï. (2019). Heavy Pnictogenium Cations as Transmembrane Anion Transporters in Vesicles and Erythrocytes. Chem 5: 2215-2227.

Plajer, A.J., J. Zhu, P. Pröhm, F.J. Rizzuto, U.F. Keyser, and D.S. Wright. (2020). Conformational Control in Main Group Phosphazane Anion Receptors and Transporters. J. Am. Chem. Soc. 142: 1029-1037.