Phosphines sulfides

Phosphates, Phosphonates, Phosphine Oxides and Phosphine Sulfides 260, 544, 1433, 1513, 1564,1658... 

This procedure also incorporates the use of bis(3-dimethylamino-propyl)phenylphosphine as a combined amine-phosphine reagent. The merits of using this basic phosphine as opposed to a tertiary amine and a phosphine lies in the ease of workup. Excess phosphine and phosphine sulfide can be removed by extraction with aqueous dilute acid. 

Examples of the intermolecular C-P bond formation by means of radical phosphonation and phosphination have been achieved by reaction of aryl halides with trialkyl phosphites and chlorodiphenylphosphine, respectively, in the presence of (TMSlsSiH under standard radical conditions. The phosphonation reaction (Reaction 71) worked well either under UV irradiation at room temperature or in refluxing toluene. The radical phosphina-tion (Reaction 72) required pyridine in boiling benzene for 20 h. Phosphinated products were handled as phosphine sulfides. Scheme 15 shows the reaction mechanism for the phosphination procedure that involves in situ formation of tetraphenylbiphosphine. This approach has also been extended to the phosphination of alkyl halides and sequential radical cyclization/phosphination reaction. ... 

Reaction of cyclic tetrasulfido complexes of heavier group 14 elements bearing bulky substituents such as Tbt(Ar)MS4 (M=Si, Ar=Tip M=Ge, Ar=Tip M=Sn, Ar=Ditp) with 3 equivalents of phosphines afforded the successful isolation of the first stable double-bonded compounds between heavier group 14 elements and sulfur atom (heavy ketones), Tbt(Ar)M=S, accompanied by the quantitative formation of the corresponding phosphine sulfides (Scheme 40) [13, 15, 112, 113]. On the other hand, their lead an-... 

P-Chirogenic phosphine/sulfide hybrid phosphine-boranes 80 were synthesized from the reaction between (l )-tosylates 79 [94] and sodium thiolate in DMF at ambient temperature as depicted in Scheme 12, or alternatively by a one pot synthesis consisting of the nucleophilic attack of the chirally induced hthium salt of 74 on phenyl disulfide. Both methodologies provided the desired sul-fide/phosphine boranes in excellent yields [10]. 

Scheme 38 Radical chain desulfurization or deselidization of phosphine sulfides or selenides to afford phosphines...

Phosphine sulfides or selenides are well-known ligands in gold(I) chemistry. With monophosphine complexes of the type [AuX(SPR3)] (X = C1, Br, CN PR3 = PPh3, PCy3, PPh2Py,... 

Other complexes with phosphine sulfides are the three coordinate [Au (S-PPh2)2C(PPh2S) (PPh2Bun)],302 the /i4-phospha-l-thiethane compound [Fe3(CO)9(/i4-PS)(AuPPh3)2] (558),3 27 and the gold(I) dendrimers containing P=NP=NP=S or P=NP=S groups as (559).3028... 

Gold(I) complexes with P,S (or Se) donor ligands are in many cases derived of phosphine sulfides or selenides as [Au2(PPh2CH2PPh2Se)2](C104)2,3140 and [Au(PPh2CH2PPh2Se)2]+ (595),1403,3141 [Au2(PPh3)2(p-SPPh2Py)](BF4)2,1427 or phosphine thioethers such as... 

The use of other phosphorus-sulfur reagents for heterocyclic synthesis appears rare. It would be interesting to investigate in more detail the reaction of compounds, such as the phosphine sulfides, with organic substrates. Triphenylphosphine sulfide is an effective sulfur transfer agent, as it converts oxiranes into thiiranes in good yield. The reaction proceeds with retention of configuration.128... 

Four-membered rings. The study of the reaction between thiobenzophenone and methylenetriphenylphosphorane177 pointed out the presence of a reactive intermediate, thiaphosphetane, which decomposed either to a thiirane and triphenylphosphine or to the Witting alkene and a phosphine sulfide, depending on the temperature. 

The heavier chalcogen and pnictogen analogues of many of these phosphine sulfides are also known (Table 1). 

Tertiary phosphine sulfides are generally stable compounds and are not easily oxidised by air, although they can be oxidised by hydrogen peroxide or dilute nitric acid. The analogous tertiary phosphine selenides and tellurides are however, more reactive to oxidation. Similar to the sulfides they can be prepared from the direct reaction of elemental chalcogen with a tertiary phosphine (Equation 1). Tertiary phosphine selenides are also accessible from tertiary phosphines using KSeCN as the selenium source instead of the element itself. 

Other related compounds are the diphosphine disulfides R2P(S)P(S)R2 14, which contain a direct phosphorus-phosphorus bond, and polysulfur fe(dior-ganophosphine sulfides) R2P(S)-S -P(S)R2 in which the two phosphorus centres are connected by a chain of one of more sulfur atoms. R2P(S)P(S)R2 compounds are accessible from heating secondary phosphine sulfides with thiophosphinic chlorides (Equation 10) or by reaction of fephosphines with... 

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