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Abstract Decarbonylation along with P‐atom transfer from the phosphaethynolate anion, PCO−, to the NbIVcomplex [(PNP)NbCl2(NtBuAr)] (1) (PNP=N[2‐PiPr2‐4‐methylphenyl]2−; Ar=3,5‐Me2C6H3) results in its coupling with one of the phosphine arms of the pincer ligand to produce a phosphanylidene phosphorane complex [(PNPP)NbCl(NtBuAr)] (2). Reduction of2with CoCp*2cleaves the P−P bond to form the first neutral and terminal phosphido complex of a group 5 transition metal, namely, [(PNP)Nb≡P(NtBuAr)] (3). Theoretical studies have been used to understand both the coupling of the P‐atom and the reductive cleavage of the P−P bond. Reaction of3with a two‐electron oxidant such as ethylene sulfide results in a diamagnetic sulfido complex having a P−P coupled ligand, namely [(PNPP)Nb=S(NtBuAr)] (4).
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Phosphonium Boranes for the Selective Transport of Fluoride Anions across Artificial Phospholipid Membranes
Abstract With the view of developing selective transmembrane anion transporters, a series of phosphonium boranes of general formula [p‐RPh2P(C6H4)BMes2]+have been synthesized and evaluated. The results demonstrate that variation of the R group appended to the phosphorus atom informs the lipophilicity of these compounds, their Lewis acidity, as well as their transport activity. Anion transport experiments in POPC‐based large unilamellar vesicles show that these main‐group cations are highly selective for the fluoride anion, which is transported more than 20 times faster than the chloride anion. Finally, this work shows that the anion transport properties of these compounds are extremely sensitive to the steric crowding about the boron atom, pointing to the crucial involvement of the Group 13 element as the anion binding site.
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- Award ID(s):
- 1856453
- PAR ID:
- 10135541
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 59
- Issue:
- 13
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 5298-5302
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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