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Triphenylphosphine sulfide (IUPAC name: triphenyl-λ 5-phosphanethione) is the organophosphorus compound with the formula (C 6 H 5) 3 PS, usually written Ph 3 PS (where Ph = phenyl). It is a colourless solid, which is soluble in a variety of organic solvents.
Triphenylphosphine reacts as a nucleophile, opening the three-membered ring to form a sulfaphosphatane. In a manner similar to the Wittig reaction, this structure then expels triphenylphosphine sulfide to produce an alkene. Barton-Kellogg reaction mechanism
The phosphorus-containing product is triphenylphosphine sulfide, Ph 3 PS. This reaction can be employed to assay the "labile" S 0 content of a sample, say vulcanized rubber. Triphenylphosphine selenide, Ph 3 PSe, may be easily prepared via treatment of PPh 3 with red (alpha-monoclinic) Se. Salts of selenocyanate, SeCN −, are used as the Se 0 ...
A phosphine sulfide is an organophosphorus compound with the formula R 3 PS. They are typically colorless, air-stable solids. A common example of a tertiary phosphine sulfide is triphenylphosphine sulfide. Phosphine sulfides are sometimes intermediates in the synthesis of tertiary phosphines. Phosphine sulfides are tetrahedral.
Wittig reagents are usually prepared from a phosphonium salt, which is in turn prepared by the quaternization of triphenylphosphine with an alkyl halide. Wittig reagents are usually derived from a primary alkyl halide. Quaternization of triphenylphosphine with secondary halides is typically inefficient.
The methylation of triphenylphosphine is the first step in the preparation of the Wittig reagent. Illustrative phosphorus(V) compounds: the phosphonium ion P(CH 2 OH) 4 +, two resonance structures for the Wittig reagent Ph 3 PCH 2, and pentaphenylphosphorane, a rare pentaorganophophorus compound. The parent phosphorane (σ 5 λ 5) is PH 5 ...
One of the first applications of phosphine ligands in catalysis was the use of triphenylphosphine in "Reppe" chemistry (1948), which included reactions of alkynes, carbon monoxide, and alcohols. [16] In his studies, Reppe discovered that this reaction more efficiently produced acrylic esters using NiBr 2 ( PPh 3 ) 2 as a catalyst instead of ...
The use of triphenylphosphine, thiourea, zinc dust, or dimethyl sulfide produces aldehydes or ketones. While the use of sodium borohydride produces alcohols. (R group can also be hydrogens) The use of hydrogen peroxide can produce carboxylic acids. Amine N-oxides produce aldehydes directly. [8]