Bis(triphenyl-λ5-phosphanylidene)ammonium hydrogendifluoride

greener alternative
PNP+[FHF]-, Bifluoride salt SuFEx catalyst, Triphenyl((triphenyl-phosphaneylidene)amino)phosphonium fluoride hydrofluoride, [Ph3P=N-PPh3]+[HF2]-
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:





reaction suitability

reagent type: catalyst

greener alternative product characteristics

Learn more about the Principles of Green Chemistry.

greener alternative category


storage temp.


General description

We are committed to bringing you Greener Alternative Products, which adhere to one or more of The 12 Principles of Greener Chemistry. This product has been enhanced for catalytic efficiency. Click here for more information.


Bifluoride salt reported by K. Barry Sharpless and colleagues as a catalyst for sulfur(VI) fluoride exchange (SuFEx)-based AA-BB polycondensation reactions to prepare polysulfonates with diverse structures, narrow polydispersity, and excellent thermal and hydrolytic stability. Bisalkylsulfonyl fluorides, the AA monomers, were prepared from ethenesulfonyl fluoride (746959) and amines/anilines while bisphenol bis(t-butyldimethylsilyl) ethers, the BB monomers, were synthesized using tert-butyldimethylsilyl chloride (190500) and bisphenols. Varying the amines, anilines, and bisphenols results in assorted polymeric backbones, including those bearing orthogonal side chains for modification post-polymerization (e.g. by CuAAC). Reaction is amenable to scale up.


13 - Non Combustible Solids

WGK Germany


Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis

Certificate of Origin

Bing Gao et al.
Nature chemistry, 9(11), 1083-1088 (2017-10-25)
Polysulfates and polysulfonates possess exceptional mechanical properties making them potentially valuable engineering polymers. However, they have been little explored due to a lack of reliable synthetic access. Here we report bifluoride salts (Q
Hua Wang et al.
Angewandte Chemie (International ed. in English), 56(37), 11203-11208 (2017-08-10)
The SuFEx-based polycondensation between bisalkylsulfonyl fluorides (AA monomers) and bisphenol bis(t-butyldimethylsilyl) ethers (BB monomers) using [Ph
Related Content
The Sharpless Lab pursues useful new reactivity and general methods for selectively controlling chemical reactions.
Read More

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Contact Technical Service