Pentafluorophenyl Diphenylphosphinate (FDPP)

Abstract

[138687-69-1] C18H10F5PO2 (MW 384.25) InChI = 1S/C18H10F5O2P/c19-13-14(20)16(22)18(17(23)15(13)21)25-26(24,11-7-3-1-4-8-11)12-9-5-2-6-10-12/h1-10H InChIKey = OOWSDKUFKGVADH-UHFFFAOYSA-N (reagent used as carboxyl activating group and coupling agent in a wide variety of amide bond formations) Solubility: soluble in most organic solvents. Form Supplied in: white powder and chunks. Handling, Storage, and Precautions: decomposition occurs upon prolonged exposure to moisture in air. Storage in a cool dry place extends the life of the reagent. The toxicological properties have not been thoroughly investigated; however, hazardous combustion products may include, but are not limited to, carbon monoxide, carbon dioxide, hydrogen fluoride, and phosphorus oxides. FDPP is incompatible with strong oxidizing agents. Physical Data: mp 47–50 °C Purification: silica gel chromatography (short column to minimize decomposition) eluting with 20% ethyl acetate in petroleum ether followed by drying under reduced pressure for 2 days over phosphorus pentoxide. Preparative Methods: FDPP can be conveniently prepared by mixing equimolar amounts of diphenylphosphinic chloride, pentafluorophenol, and imidazole in anhydrous CH2Cl2 at room temperature (eq 1).1 There are slight procedural variations in the literature as to order of addition and reaction duration.2, 3 It has been found that using an excess of the diphenylphosphinic chloride (1.5–2 equiv) to drive the reaction to completion simplifies the purification, as the residual hydrolyzed reagent adheres tightly to the silica gel column and is, therefore, easier to separate than residual pentafluorophenol.4 (1)