Triphenylphosphine platinum

Tetrakis(triphenylphosphine) platinum [14221-02-4] M 1244.3, m 118". Recrystd by adding hexane to a cold saturated solution in CgHg. It is soluble in C Hg and CHCI3 but insoluble in EtOH and hexane. A less pure product is obtained if crystd by adding hexane to a CHCI3 soln. Stable in air for several hours and completely stable under N2. [7 Am Chem Soc 2323 7958.J... 

Platinum, ethylenebis(triphenylphosphine)-reactions with 5,6-dimethyl-2,l,3-benzothiadiazole, 2. 

Acyl chlorides containing an a hydrogen are smoothly converted to alkenes, with loss of HCI and CO, on heating with chlorotris(triphenylphosphine)rhodium, with metallic platinum, or with certain other catalysts. The mechanism probably involves conversion of RCH2CH2COCI to RCH2CH2—RhCO(Ph3P)2Cl2 followed by a concerted syn elimination of Rh and H. See also 14-39 and 19-12. 

Non-ionic thiourea derivatives have been used as ligands for metal complexes [63,64] as well as anionic thioureas and, in both cases, coordination in metal clusters has also been described [65,66]. Examples of mononuclear complexes of simple alkyl- or aryl-substituted thiourea monoanions, containing N,S-chelating ligands (Scheme 11), have been reported for rhodium(III) [67,68], iridium and many other transition metals, such as chromium(III), technetium(III), rhenium(V), aluminium, ruthenium, osmium, platinum [69] and palladium [70]. Many complexes with N,S-chelating monothioureas were prepared with two triphenylphosphines as substituents. 

A stoichiometric reaction of tetrakis(triphenylphosphine)platinum(0) with bis(pinacolato)diboron gives cis-diborylplatinum(n) complex in high yield (Scheme 3).38 The diborylplatinum complex then reacts with an alkyne, giving m-diboration product.40,41 These results indicate that the diboration proceeds through the general mechanism shown in Scheme 1 (E1 = E2 = Bpin), which involves the formation of diborylplatinum(n), insertion of an alkyne into the B-Pt bond, and reductive elimination. 

Many catalysts, certainly those most widely used such as platinum, palladium, rhodium, ruthenium, nickel, Raney nickel, and catalysts for homogeneous hydrogenation such as tris(triphenylphosphine)rhodium chloride are now commercially available. Procedures for the preparation of catalysts are therefore described in detail only in the cases of the less common ones (p. 205). Guidelines for use and dosage of catalysts are given in Table 1. 

Oriho-vinylbenzenethiol forms similar polymeric and hexameric complexes (55) which can be converted to monomers by reaction with two moles of triphenylphosphine per platinum. Attempts were made to remove one phosphine to give a chelate, using anhydrous silver perchlorate the product isolated had the unusual structure shown in Fig. 41. 

The triphenylphosphine complex 42 b reacts with bromine to give a platinum(IV) species 42f, assigned the cyclic structure with four platinum-carbon c-bonds. The reaction sequence here must begin with the attack of a bromine molecule on an uncoordinated olefin, as otherwise it is hard to see why two metal-carbon bonds are formed, and not one metal-carbon and one metal-bromine. 

PtCl P(C6H5)3 ]2(p-Cl)2] di-p-chloro-bis[chloro(triphenylphosphine)platinum]... 

A. CHLORO(DIMETHYL HYDROGEN PHOSPHITE-P) (DIMETHYL PHOSPHITO-/ ) (TRIPHENYLPHOSPHINE) PLATINUM(II)... 

Bis(dimethyl hydrogen phosphite-/ )bis(dimethyl phosphito-P)platinum(lI) (0.420 g, 0.66 mmole) and c/s-[dichlorobis(triphenylphosphine)platinum(ll)] (0.524 g, 0.66 mmole) are refluxed in toluene (25 mL) for 30 hours. The colorless reaction mixture is filtered while hot using vacuum to remove any unreacted c/s-[dichlorobis(triphenylphosphine)platinum(Il)]. The filtrate is transferred to a 100-mL, round-bottomed flask and evaporated to dryness on a rotary evaporator, using gentle heating if necessary. The cream-colored residue is dissolved in a mixture of dichloromethane (15 mL) and methanol (15 mL) and the solution is allowed to concentrate slowly under water aspirator vacuum on a rotary... 

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