white to off-white crystalline powder
Intermediate in antifouling paint agents; catalyst in organic reactions.
Phenylphosphonic acid additive used with Noyori's catalyst for oxidation of sulfides to sulfones. Used as additive of unsaturated polyester PU resin. It also can be added into nylon to improve its polymerization degree. It can be used as extreme pressure agent of lube; used as catalyst of carboxylic acid & alcohol reaction; it can be used as fire retarding treatment of fiber used asganic materials.
ChEBI: Phenylphosphonic acid is a member of benzenes.
It is best to recrystallise it from H2O by concentrating an aqueous solution to a small volume and allowing to crystallise. Wash the crystals with ice cold H2O and dry them in a vacuum desiccator over H2SO4. [Lecher et al. J Am Chem Soc 76 1045 1954.] pK2 5 values in H2O are 7.07, and in 50% EtOH 8.26. [Jaffé et al. J Am Chem Soc 75 2209 1953, IR: Daasch & Smith Anal Chem 23 853 1951, Beilstein 16 IV 1068.]