Scrabble?! PHOSPHONIUM

Definitions of PHOSPHONIUM in various dictionaries:

The phosphonium (more obscurely: phosphinium) cation describes polyatomic cations with the chemical formula PR+4. A phosphonium salt is a salt containing either the phosphonium (PH4+) ion, such as phosphonium iodide (PH4+I) or, more commonly, an organic derivative such as the quaternary phosphonium salts tetraphenylphosphonium chloride, (C6H5)4P+ Cl and tetramethylphosphonium iodide, [P(CH3)4]+I. Salts of the parent PH+4 are rarely encountered, but this ion is an intermediate in the preparation of the industrially useful tetrakis(hydroxymethyl)phosphonium chloride: PH3 + HCl + 4 CH2O P(CH2OH)+4Cl Organic phosphonium salts are common reagents in the laboratory. Those with a PH bond are produced through protonation of phosphines: PR3 + H+ HPR+3 Many organic quaternary phosphonium cations (PR+4) are produced by alkylation of organophosphines. For example, the reaction of triphenylphosphine with methyl iodide gives methyltriphenylphosphonium iodide, the precursor to a Wittig reagent: PPh