Fluoride ion chelation by a bidentate phosphonium/borane Lewis acid. Academic Article

abstract

• The phosphonium borane [1-Mes2B-2-MePh2P-(C6H4)]+ ([2]+) has been synthesized as an iodide salt by alkylation of 1-Mes2B-2-Ph2P-(C6H4) with MeI. This novel cationic borane complexes fluoride to afford the corresponding zwitterionic fluoroborate complex 1-FMes2B-2-MePh2P-(C6H4) (2-F) with a binding constant in MeOH exceeding that of 1-Mes2B-4-MePh2P-(C6H4) ([1]+) by at least 4 orders of magnitude. Structural and computational results indicate that the high fluorophilicity of [2]+ arises from both Coulombic and cooperative effects which lead to formation of a B-F-->P interaction with a F-->P distance of 2.666(2) A. These results, which are supported by NBO and AIM analyses, show that the latent phosphorus-centered Lewis acidity of the phosphonium moiety in [2]+ can be exploited to enhance fluoride binding via chelation.

authors

• Gabbai, Francois

published proceedings

• J Am Chem Soc

author list (cited authors)

• Hudnall, T. W., Kim, Y., Bebbington, M., Bourissou, D., & Gabbai, F. P.

citation count

• 208

complete list of authors

• Hudnall, Todd W||Kim, Young-Min||Bebbington, Magnus WP||Bourissou, Didier||Gabbaiï, François P

publication date

• August 2008

publisher

• American Chemical Society (ACS)  Publisher

published in

• Journal of the American Chemical Society  Journal

keywords

• Acids
• Boranes
• Chelating Agents
• Crystallography, X-Ray
• Fluorides
• Ions
• Models, Chemical
• Models, Molecular
• Molecular Structure
• Organophosphorus Compounds

PubMed Central ID

• 18652460

Digital Object Identifier (DOI)

• 10.1021/ja804492y

start page

• 10890

end page

• 10891

volume

• 130

issue

• 33