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Phosphine oxides perfluorinated

Hydrolysis of alkyl-substituted phosphine oxides is generally difficult, heating with solid sodium or potassium hydroxide is needed in order to break the P—C bond. Hydrolysis of phosphonates and phos-phinates occurs with P—O cleavage in preference to P—C cleavage. Exceptions have been reported with several aromatic phosphine oxides containing p- and o-nitrobenzyl groups and other stabilized systems. Perfluorinated phosphine oxides can also be hydrolyzed to the phosphinic and phosphonic acids.2 ... [Pg.864]

One of the main drawbacks of the Wittig reaction is the formation of unwanted triphenylphosphine oxide. A new route, which makes use of polymer-supported triphenylphosphine and microwave dielectric heating has been developed (Scheme 13), which yields the required alkene without the triphenylphosphine oxide. An alternative strategy for separation of the product alkene from unwanted phosphine oxide by-product is to carry out the Wittig reaction in a fluorous solvent using a perfluorinated ylide such as (45). One drawback of this... [Pg.616]

Sinou et al. have developed a Wittig reaction of stabilized perfluorinated phos-phonium ylides with aldehydes performed in a perfluorosolvent. This protocol allows an easy separation of the alkene product from the perfluorinated phosphine oxide byproduct by simple liquid-liquid extraction [149]. [Pg.218]

The extraction of iron(III), mercury, arsenic and tin ions from aqueous (acidic) solutions was accomplished with tri-ra-oetylphosphine oxide. This phosphine oxide was also found suitable to extraet phenol from aqueous solutions. More specialized phosphine oxides were useful for rare-earth metal extraction. Perfluorinated phosphine oxides and sulfides served as extractants for gold(III), heavy metals and radionuelides. ... [Pg.76]

Aqua(phosphine)ruthenium(II) complexes [121] are useful for activation of molecular oxygen, and catalytic oxidation of cyclohexene can be carried out with 1 atm of O2 [121a,bj. The ruthenium catalyst bearing perfluorinated 1,3-diketone ligands catalyzes the aerobic epoxidation of alkenes in a perfluorinated solvent in the presence of i-PrCHO [122]. Asymmetric epoxidations of styrene and stilbene proceed with 56-80% e.e. with ruthenium complexes 38-40 (Figure 3.2) and oxidants such as PhI(OAc)2, PhIO, 2,6-dichloropyridine N-oxide, and molecular oxygen [123-125]. [Pg.74]


See other pages where Phosphine oxides perfluorinated is mentioned: [Pg.56]    [Pg.21]    [Pg.31]    [Pg.51]   


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