Tetrapropylammonium perruthenate (TPAP or TPAPR) is the chemical compound described by the formula N(C3H7)4RuO4. Sometimes known as the Ley–Griffith reagent, this ruthenium compound is used as a reagent in organic synthesis. This salt consists of the tetrapropylammonium cation and the perruthenate anion, RuO−4.
Uses
Ruthenium tetroxide is a highly aggressive oxidant, but TPAP, which is its one-electron reduced derivative, is a mild oxidizing agent for the conversion of primary alcohols to aldehydes (the Ley oxidation).[1] Secondary alcohols are similarly oxidized to ketones.[2] It can also be used to oxidize primary alcohols all the way to the carboxylic acid with a higher catalyst loading, larger amount of the cooxidant, and addition of two equivalents of water. In this situation, the aldehyde reacts with water to form the geminal diolhydrate, which is then oxidized again.[3]
^Ley, Steven V.; Norman, Joanne; Griffith, William P.; Marsden, Stephen P. (1994). "Tetrapropylammonium perruthenate, Pr4N+RuO4−, TPAP: A catalytic oxidant for organic synthesis". Synthesis. 1994 (7): 639–666. doi:10.1055/s-1994-25538. S2CID95136192. (review article)
^Xu, Z.; Johannes, C. W.; Houri, A. F.; La, D. S.; Cogan, D. A.; Hofilena, G. E.; Hoveyda, A. H. (1997). "Applications of Zr-catalyzed carbomagnesation and Mo-catalyzed macrocyclic ring closing metathesis in asymmetric synthesis. Enantioselective total synthesis of Sch 38516 (Fluvirucin B1)". J. Am. Chem. Soc.119 (43): 10302–10316. doi:10.1021/ja972191k.
^Griffith, William P.; Ley, Steven V.; Whitcombe, Gwynne P.; White, Andrew D. (1987). "Preparation and use of tetra-n-butylammonium per-ruthenate (TBAP reagent) and tetra-n-propylammonium per-ruthenate (TPAP reagent) as new catalytic oxidants for alcohols". J. Chem. Soc., Chem. Commun. (21): 1625–1627. doi:10.1039/C39870001625.
