One triphenylbis(fluoroalkoxy)phosphorane, Ph.sub.3 P(OCH.sub.2 CF.sub.3).sub.2, has been disclosed in the literature. See the following references a-d:
a) N. Lowther and C. D. Hall, J. Chem. Soc., Chem. Comm., 1303 (1985) describe the preparation of Ar.sub.3 P(OCH.sub.2 CF.sub.3).sub.2 (Ar=substituted phenyl rings) by the reaction of Ar.sub.n P(OR).sub.n-3 (n=0 to 3) with PhSOCH.sub.2 CF.sub.3 and the mechanisms in the hydrolysis of these phosphoranes. PA1 b) M. Von Itzstein and I. D. Jenkins, Aust, J. Chem., 36, 557 (1983), disclose a method for the preparation of dialkoxytriphenylphosphoranes by the reaction of Ph.sub.3 P with alcohols in the presence of azodicarboxylates and the mechanism for this reaction. This paper deals mainly with hydrocarbon phosphoranes and only one fluorinated compound Ph.sub.3 P(OCH.sub.2 CF.sub.3)2 was described. The fluorinated compound is prepared either by their new method or reaction of Ph.sub.3 PBr.sub.2 and CF.sub.3 CH.sub.2 OH in the presence of Et.sub.3 N. The later reaction is the same as that used herein. PA1 c) D. B. Denney et al., J. Am. Chem. Soc., 103, 1785 (1981) report the preparation of phosphoranes containing the trifluoroethoxy group and the reaction of these fluorinated phosphoranes with alkoxides such as trifluoroethoxide. PA1 d) T. Kubota et al., J. Org. Chem., 45, 5052 (1980) used bis (2,2,2-trifluoroethoxy)triphenyl- phosphorane as a condensation reagent for alcohols with thiols. The preparation of Ph.sub.3 P(OCH.sub.2 CF.sub.3).sub.2 and application of this reagent in organic synthesis is described in detail. These researchers prepared Ph.sub.3 P(OCH.sub.2 CF.sub.3).sub.2 from the reaction of Ph.sub.3 PBr.sub.2 and NaOCH.sub.2 CF.sub.3 and investigated the reactions of Ph.sub.3 P(OCH.sub.2 CF.sub.3)2 with alcohols, carboxylic acid, thiols and amines. This reference also mentions the reaction of Ph.sub.3 P(OCH.sub.2 CF.sub.3).sub.2 with hydrocarbon aldehydes to give the corresponding acetals. PA1 e) Yu. G. Shermalovich et al., Zh. Org. Khim, 52, 2526 (1982) report that (CF.sub.3).sub.2 C(OCH.sub.2 CF.sub.2 CF.sub.2 H).sub.2 has been prepared from the reaction of hexafluoroacetone (HFA) and P(OCH.sub.2 CF.sub.2 CF.sub.2 H).sub.5 The reaction of P(OCH.sub.2 Rf).sub.5 (Rf=((CF.sub.2)nH, n=2,4) with carbonyl compounds is reported. Although the one mentioned fluorinated ketal, (CF.sub.3).sub.2 C(CH.sub.2 CF.sub.2 CF.sub.2 H).sub.2, was prepared by reaction of P(OCH.sub.2 CF.sub.2 CF.sub.2 H).sub.5 with hexafluoroacetone, the starting material used was different from that used herein; applicant's starting material is Ph.sub.3 P(OCH.sub.2 Rf).sub.2. Applicant believes that the method reported could not be adapted to prepare (CF.sub.3).sub.2 (OCH.sub.2 CF.sub.3).sub.2 by the reaction of HFA with P(OCH.sub.2 CF.sub.3).sub.5.
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