Polyfluoroalkyl Dibasic Acid Phosphates, Bis(polyfluoroalkyl) Monobasic Acid Phosphates, and Their Precursors

Abstract

The new dibasic acid phosphates RfOP(O)(OH)2(Rf = (CF3)2CH and CF3(CH3)CH) and monobasic acid phosphates (RfO)2P(O)OH (Rf = CF3(CH3)CH, (CF3)2CH, (CF3)2CH3C, CF3(CH3)2C), as well as new routes to CF3CH2OP(O)(OH)2, (CF3CH2O)2P(O)OH, and [H(CF2)4CH2O]2P(O)OH, are reported. When heated in the presence of water at 80–100 °C, (RfO)2P(O)OH is hydrolyzed to RfOP(O)(OH)2, which is converted to H3PO4at higher temperatures. The dibasic acid phosphates RfOP(O)(OH)2(Rf = (CF3)2CH3C, CF3(CH3)2C) undergo dehydration to form [RfOP(O)(OH)]2O. Additionally, the chloro precursors to these acids have been synthesized, including the (polyfluoroalkyl) dichlorophosphinites, RfOPCl2(Rf = CF3CH2, CF3(CH3)CH, (CF3)2CH, (CF3)2CH3C, CF3(CH3)2C), and bis(polyfluoroalkyl) chlorophosphonites, (RfO)2PCl (Rf = CF3CH2, (CF3)2CH3C, CF3(CH3)2C). If dinitrogen tetraoxide is used as an oxidant, the former are converted to RfOP(O)Cl2and the latter to (RfO)2P(O)Cl. Lithium polyfluoroalkoxides with PC13 give tris(polyfluoroalkyl) phosphites, (RfO)3P (Rf = CF3(CH3)CH, (CF3)2CH3C, CF3(CH3)2C, CF3CH2, (CF3)2CH), which can be oxidized to (RfO)3PO phosphates with N2O4. In some cases, (RfO)2PCl (Rf = (CF3)2CH3C, CF3(CH3)2C) gives tetrakis(polyfluoroalkyl) diphosphates, (RfO)2P(O)OP(O)(ORf)2, and CF3CH2OPCl2gives CF3CH2OP(O)(μ-o)2P(O)OCH2CF3. The (RfO)3P phosphites (Rf= CF3CH2, CF3(CH3)CH, (CF3)2CH3C, CF3(CH3)2C) undergo Arbuzov rearrangements with Cl2to form (RfO)2P(O)Cl. Hydrogen chloride converts [CF3(CH3)2CO]3P to [CF3(CH3)2CO]2P(O)H, which with chlorine forms [CF3(CH3)2CO]2P(O)Cl. © 1986, American Chemical Society. All rights reserved.