Phosphotungstic Acid Hydrate

Phosphotungstic acid [1343-93-7] H3PW12O40 (MW 2880.2) InChI = 1S/H3O4P.36O.12W/c1-5(2,3)4;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;/h(H3,1,2,3,4);;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; InChIKey = IYDGMDWEHDFVQI-UHFFFAOYSA-N Phosphotungstic Acid Hydrate [12501-23-4] H3PW12O40·24H2O (MW 3312.2) InChI = 1S/H3O4P.24H2O.36O.12W/c1-5(2,3)4;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;/h(H3,1,2,3,4);24*1H2;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; InChIKey = HBHUCUXSBGOMGF-UHFFFAOYSA-N Phosphotungstic Acid 44-Hydrate [12067-99-1] InChI = 1S/H3O4P.44H2O.36O.12W/c1-5(2,3)4;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;/h(H3,1,2,3,4);44*1H2;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; InChIKey = ZVAATTKWJSOPMK-UHFFFAOYSA-N (reagent used as a recyclable superacid catalyst in solution or supported on silica or alumina. It has been utilized as a superacid for isomerization of cycloalkanes, as an acid catalyst for Prins cyclization reactions, dehydration of alcohols, hydration of olefins, and has also been utilized in oxidations of ketones to aldehydes and carboxylic acids) Chemical Name: Tungstate(3−), tetracosa-μ-oxododecaoxo[μ12-[phosphato(3−)-κO:κO:κO:κO′:κO′:κ′;O″:κO″:κO″:κO″:κO″′:κO″′:κO″′]]dodeca-, trihydrogen. Alternate Names: dodecatungstophosphoric acid; 12-phosphotungstic acid; 12-tungstophosphoric acid; phosphotungstic acid; tungstophosphoric acid; tungsten hydroxide oxide phosphate; tungsten hydrogen oxide phosphate; phosphowolframic acid; phosphotungstic acid 44-hydrate. Common Abbreviations: PTA, PWA, TPA. Physical Data: mp 89 °C (hydrate). Solubility: soluble in H2O (1 g mL−1). Preparative Method: phosphotungstic acid can be prepared by the reaction of sodium tungstate (Na2WO4·2H2O) with phosphoric acid (H3PO4) acidified with hydrochloric acid (HCl).1 Form Supplied in: colorless to gray, pale yellow, or slightly yellow-green, odorless crystals. It is also available as a 10% aqueous solution. Purification: a few drops of conc. nitric acid (HNO3) are added to 100 g of phosphotungstic acid dissolved in 75 mL of water in a separatory funnel, and the solution is extracted with diethyl ether. The lowest of the three layers, which contains a phosphotungstic acid–ether complex, is separated and washed three times with 2 M HCl, then with water and again extracted with ether. Evaporation of the ether under vacuum with mild heating on a water bath gives crystals, which are dried under vacuum and ground.2 Dehydration: solid PTA is heated at 150–300 °C under vacuum for 1–2 h.3 Handling, Storage, and Precautions: use only in a well-ventilated area. Minimize dust generation and accumulation. Avoid heating above 400 °C due to decomposition and generation of toxic fumes. Avoid contact with eyes, skin, or clothing. Do not ingest or inhale. Keep container closed when not in use. Store refrigerated at 4 °C. If material is stored slightly above room temperature, it will dissolve in its own water of hydration. Hygroscopic, may contain a large amount of water of hydration (up to 48 moles of water per mole of phosphotungstic acid). Precautions: toxic and irritant; inhalation, ingestion, or skin contact with material may cause severe injury or death. Effects of contact or inhalation may be delayed. Phosphotungstic acid is a strong oxidizing agent in aqueous solutions. Substance itself is noncombustible but may decompose upon heating above 400 °C to give toxic and/or irritating fumes.