Phosphines bidentate tertiary

Pt(en)(N03)2] and [Pt(OTf)2L2] (L = mono- or 1/2 bidentate tertiary phosphine) or dinuclear complexes of the type [Pt2(OTf)2(/i-monodentate tertiary phosphine cr-aryl = 4, -biphenyl, / -terphenyL 4,4 -benzophenone, etc.) other structural motifs employing platinum(II) have also been reported.2 0 The addition of bridging, multidentate N-donor ligands of various shapes and sizes to the labile complexes in a suitable solvent system has afforded several classes of discrete, plat-inum(II)-containing polygons, polyhedra, and catenanes. 

New reproducible syntheses of platinum(II) carbonato complexes of the type [Pt(C03)L2] (L mono- or bidentate tertiary phosphine) involve the reaction of Ag2C03 with [PtCl2L2] in water-saturated CH2C12 solution.3 Other methods of preparation include the conversion of the dichloroplatinum(II) complexes to the corresponding bis(alkoxo)- or bis(phenoxo)-platinum(II) species, followed by hydrolysis in the presence of C02. 

Complexes with bidentate tertiary phosphines, arsines and stibines 116... 

A large number of nickel(II) complexes with bidentate tertiary phosphines and arsines have been prepared and characterized since the initial reports on o-phenylenebisdimethylarsine and 1,2-bisdiphenylphosphinoethane (Table 64 XVIII, III) by Chatt and Mann,1267 and Wymore and Bailar126 respectively. The most common diphosphines, diarsines, distibines and mixed donor ligands are collected in Table 64 and selected nickel(II) complexes are reported in Table 65. 

Reaction of Mo(Nj)2L2, where L is a bidentate tertiary phosphine ligand, occurs... 

Platinum(II) complexes of formula Pt(LL)Cl(Ph) or Pt(LL)Ph2 have been reported to be unreactive toward carbon monoxide when LL is a bidentate tertiary phosphine of the type Ph2P(CH2) PPh2, n = 1 or 2. 

Polydentate phosphines continue to attract much interest, especially in the complexes they form, and also in the catalytic applications displayed by some compounds.214-216 To differentiate this class from that of Section 1.12.2.7 on bidentate tertiary phosphines, polyphosphines are compounds possessing three or more phosphorus donor atoms. Most synthetic routes are similar to those outlined before,50,216 so only a selection of polydentate phosphines will be given here including a brief summary, where appropriate, of their syntheses and key reactions. 

Cu H2B(tzN02)2 (PR3)2], [Cu H2B(tzN02)2 (dppe)] and [Cu H2-B(tzN°2)2 (PR3)] have been synthesized from the reaction of CuCl with K H2B(tzN°2)2, and mono or bidentate tertiary phosphines. Selected complexes have also been tested against a panel of several human tumor cell lines.222... 

Silver(I) derivatives containing bidentate tertiary phosphines and pzTp have been prepared from AgN03 and dppe, and dppf. Their solid state and solution properties have been investigated through analytical and spectroscopic measurements. The structures of [Ag(pzTp)(dppf)] have been determined by single-crystal X-ray studies, the tetrakis(pyrazolyl)borate being always bidentate with the silver(I) center in distorted tetrahedral geometries. 

Stelzer and co-workers reported a number of chiral water-soluble secondary phosphines [14], prepared by nucleophilic phosphination of primary phosphines with fluorinated aryl sulfonates in the superbasic medium DMSO/KOH. Further reaction with alkyl halides gives bidentate tertiary phosphines with P-chirality, but only racemic versions have been reported so far. Hanson et al. introduced so-called surface-active phosphines into asymmetric aqueous-phase catalysis. One of the main problems inherent to two-phase catalysis is the often very low miscibility of the substrates in the aqueous phase. Insertion of long alkyl chains between phosphorus atoms and phenyl groups in sulfonated phosphine ligands has been proven to increase reaction rates in the Rh-catalyzed hydroformylation of 1-octene [15], This concept was extended to a number of chiral ligands, i.e., the monoden-... 

Complexes with monodentate tertiary phosphines, arsines and stibines Complexes with alkyl and aryl phosphites as ligands Complexes with bidentate tertiary phosphines, arsines and stibines... 

In the early 1980s. it was discovered that cationic palladium catalysts with bidentate tertiary phosphines exhibited remarkable reaction rates for olefin/... 

It is evident that by substituting bidentate tertiary phosphine ligands for monophosphines it is possible to cause major changes in the reactivity of a metal-phosphine complex. We discuss in other sections the contrasting profile of biological activity of chelated diphosphine complexes compared to related monophosphine complexes. 

The enthalpies of reaction of [Cp Ru(ti4.C0D)Cl] with a series of bidentate tertiary phosphine ligands to yield [Cp Ru(PP)Cl] (PP = dppm, dmpm, dppe, dppp, depe) have been measured by anaerobic solution calorimetry. Comparison of the enthalpies of reaction with those of monodentate phosphine ligands afforded a quantitative treatment of ring strain energies in the... 

A bidentate phenanthroline would involve considerable non-bonding interactions between the tertiary phosphines and the benzene rings [91]. 

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