Sulfonated triphenyl phosphines

Although rhodium recovery is efficient it is difficult to separate it from heavies that are formed in small amounts. Over time these heavies tend to result in some catalyst deactivation. One solution to this problem has been developed by Ruhrchemie/Rhone-Poulenc. In this process sulfonated triphenyl phosphine is used as the ligand, which imparts water solubility to the catalyst. The reaction is two-phase, a lower aqueous phase containing the catalyst and an upper organic phase. Fortunately the catalyst appears to sit at the interface enabling reaction to proceed efficiently. At the end of... 

These polymers show lower water uptake than the analogous sulfonated poly(arylene ether sulfone) materials, possibly suggesting some interaction between the aromatic nitrile and sulfonic acid. The phosphine oxide functional moiety could also be used as a compatibilizer with other materials. Sulfonated poly(arylene ether phosphine oxide sulfone) terpoly-mers have been prepared both with sulfonated triphenyl phosphine oxide and with triphenyl phosphine oxide with 3,3 -disulfonate-4,4 —dichlorodiphenyl sulfone as the sulfonic acid bearing monomer. Block copolymers containing phosphine oxide appear to avoid the ether—ether interchange that results when non—phosphine oxide blocks are utilized, and this is being further pursued. ... 

RCH/RP [Ruhrchemie/Rhone Poulenc] A variation of the 0X0 process in which the triphenyl phosphine (part of the Wilkinson catalyst) is sulfonated, in order to render the catalyst soluble in water for easier recovery. First commercialized in 1984 for the manufacture of butyraldehyde. 

Thiols can be prepared by the reduction of sulfonyl halides652 with LiAIH4. Usually, the reaction is carried out on aromatic sulfonyl chlorides. Zinc and acetic acid, and HI. also give the reduction. Sulfonic acids have been reduced to thiols with a mixture of triphenyl-phosphine and either Ii or a diaryl disulfide.633 Disulfides RSSR can also be produced.634 For the reduction of sulfonyl chlorides to sulfinic acids, see 0-118. 

Recently the use of allylic halide (see compound 96, Scheme 34) or sulfonate for the introduction of a malonyl residue at C-2 of pyranose derivatives using tetrakis(triphenyl-phosphine)palladium complex has been reported [132]. In this case, the malonyl chain is introduced anti to the leaving group at the 7-position. 

Dimethylthexylsilyl trifluoromethane-sulfonate, 74 Diphenylsilane, 153 Diphenylsilane-Di- x-chlorobis(l,5-cyclooctadiene)dirhodium, 153 Diphenylsilane-Palladium(II) chloride-Triphenylphosphine, 126 Diphenylsilane-Tetrakis(triphenyl-phosphine)palladium(0)-Zinc chloride, 126... 

Researchers have worked to alleviate the problems of separation and corrosion in processes such as the oxo process by designing catalysts that are confined in a separate phase from the reactants (see Section 14.2.4). A commercially successful approach for propene hydroformylation resulted from preparation of water-soluble rhodium complex catalysts by sulfonation of the phenyl rings of the triphenyl phosphine ligands. The catalyst is used in a reactor with two liquid phases the propene is concentrated in the organic phase and the catalyst in the aqueous phase near the interface. The CO -I- H2 is bubbled into a mixed reactor, and the two-phase liquid product flows to a settler the organic product flows to downstream separation devices, and the aqueous phase with the catalyst is recycled to the reactor. 

Attempts to convert the sulfones back into PASHs have been successful with a number of agents such as various metals (zinc, tin, magnesium, aluminum, iron, and nickel) in acetic acid, palladium on carbon with hydrazine, stannous chloride, lithium triethylborohydride, diphenylsi-lane, sodium borohydride, boron trifluoride, dicyclohexylcarbodiimide, triethyl phosphite, dimethyl dichlorosUane with lithium aluminum hydride, diphenylsilane, and triphenyl phosphine with iodine. However, none of them cleanly effect this conversion. 

The sulfonation of triphenyl phosphine with fuming sulfuric acid can give three possible products monosulfonated triphenylphosphine (TPPMS), disulfonated triphenylphosphine (TPPDS), and TPPTS 1, depending on the reaction conditions (Figure 9). Using this method many sulfonated aryl phophines have been prepared (2b,... 

Bisphenol A based poly(arylene ether triphenylphosphine oxide/diphenyl sulfone) copolymers were solution blended with Bisphenol A dimethacrylate vinyl ester/styrene and cured with peroxide [921]. Increasing the triphenyl phosphine oxide content in the copolymer yielded improved solubihty in the vinyl ester/styrene mixture as well as the apparent miscibility of the crosslinked blend. With 100% triphenyl phosphine oxide in the copolymer, transparent blends with the cured vinyl ester were observed. Intermediate levels of the triphenyl phosphine oxide, however, gave the best fracture toughness (controlled phase separation appeared to be desired). 

Shobha, H.K., Sankarapandian, M., Glass, T.E., McGrath, J.E. (2000) Synthesis and characterization of sulfonated poly(arylene ether)s based on functionalized triphenyl phosphine oxide for proton exchange membranes. Polymer Preprints, 41, 1298-1299. 

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