Triphenylphosphine, sulfonation

TPPMS triphenylphosphine sulfonate, sodium salt PPh2(C6H4S03Na)3... 

An elegant synthesis method which is specific to sulfone polymers containing phenyl—phenyl linkages (such as PPSF) is the nickel-catalysed coupling of aryl dihahdes. The scheme for this synthesis involves a two-step process. First, an aromatic dihaUde intermediate is formed which carries the backbone features of the desired polymer. This aromatic dihahde intermediate is then self-coupled in the presence of sero-valent nickel, triphenylphosphine, and excess sine to form the biphenyl- or terphenyl-containing polymer. AppHcation of this two-step scheme to PPSF can be depicted as follows ... 

Sulfonic acids are prone to reduction with iodine [7553-56-2] in the presence of triphenylphosphine [603-35-0] to produce the corresponding iodides. This type of reduction is also facile with alkyl sulfonates (16). Aromatic sulfonic acids may also be reduced electrochemicaHy to give the parent arene. However, sulfonic acids, when reduced with iodine and phosphoms [7723-14-0] produce thiols (qv). Amination of sulfonates has also been reported, in which the carbon—sulfur bond is cleaved (17). Ortho-Hthiation of sulfonic acid lithium salts has proven to be a useful technique for organic syntheses, but has Httie commercial importance. Optically active sulfonates have been used in asymmetric syntheses to selectively O-alkylate alcohols and phenols, typically on a laboratory scale. Aromatic sulfonates are cleaved, ie, desulfonated, by uv radiation to give the parent aromatic compound and a coupling product of the aromatic compound, as shown, where Ar represents an aryl group (18). 

A, A, A, A -tetramethylethylenediamine trimethyl orthoformate tetrapropylammonium perruthenate tetraphenylporphyrin sulfonated triphenylphosphine triisopropylbenzensulfonyl chloride triphenylcarbenium tetrafluoroborate tetrabutylammonium triphenylmethanethiolate toluenesulfonyl... 

Sodium salts of sulfonated triphenylphosphine P(m-C5H4S03Na)3 or alkyltriphenyl-methyltrisulfonates function as stabilizers for hydrosols of colloidal rhodium and (C6H5)2P-p-C6H5S03Na has been used by Schmid to prepare water soluble gold clusters which are isolable and redispersible without agglomeration [202]. 

Amatore et al. developed an aqueous cross-coupling reaction of terminal alkynes with 1-iodoalkynes using a water-soluble Pd(0) catalyst prepared in situ from Pd(OAc)2 and sulfonated triphenylphosphine P(C6H4 — m-SCENa (TPPTS) without Cu(I) promoter, giving diynes with moderate yields (43-65%)(Eq. 4.22) 42... 

Desulfuration.1 This complex as such or in combination with 2,2 -bipyridyl (bpy) or triphenylphosphine (a NiCRAL) can effect desulfuration of heteroarenes. aryl thioethers, dithioketals, sulfoxides, or sulfones in DME or THF at 63° in 1.5-30 hours. NiCRA is sufficient for aryl thioethers, dithioketals, but NiCRALs are more efficient for desulfuration of heteroarenes. Yields can be comparable with those obtained with Raney nickel. 

The solubility of these phosphine ligands in water can be extraordinarily high. The sodium salt of the ira-sulfonated triphenylphosphine (tppts) has a solubility in water of 1.1 kg 1 1 [20], Apart from high solubility, these sulfonated phosphines are widely used for several reasons including ... 

With this last point in mind, the synthesis of mono-, bis- and tra-sulfonated triphenylphosphine will be described, but the same methodology can be applied to the preparation of other sulfonated arylphosphines. In general, these phosphines are made by direct sulfonation using fuming sulfuric acid (oleum) [21], The extent of sulfonation is determined by the SO3 strength, as well as factors such as the temperature and time of the reaction. The monosulfonated phosphine (tppms) is prepared using oleum of 20% SO3 strength, with typically 30% SO3 used... 

TPPMS triphenylphosphine-3-sulfonic acid lithium salt... 

Fuming sulfuric acid (oleum) of 20% SO3 strength is suitable for preparation of monosulfonated products [1-3] while for multiple sulfonation 30% (or more) SO3 is required [4-10], The phosphine is dissolved in cold oleum with protonation of the phosphoms atom therefore in cases when the phenyl rings are directly attached to the phosphoms (e.g. triphenylphosphine or the bis(diphenylphosphino)alkanes) sulfonation takes place in the 3-position. 

The peroxide 75 reacts with triphenylphosphine to afford the cyclic siloxane 76 and with dimethyl snlfide in petrolenm ether at 50 °C to give dimethyl sulfoxide (19%), dimethyl sulfone (15%) and ca 50% of a nonperoxidic polymer 77. 

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