Phosphine ditertiary

J. Chatt and H. R. Watson, Complexe.s of zerovalent transition metals with the ditertiary phosphine, Me2PCH2CH2PMe2, J. Chem. Soc. 2545-9 (1962). 

Other dichloro(ditertiary phosphine)nickel(II) complexes (see Table VI) catalyze both hydrosilylation and H/Cl exchange, but analogous complexes containing monodentate phosphine ligands or bidentate amine groups are essentially inactive (173). 

The ditertiary phosphines (11), prepared from the corresponding alkyl chloride and lithium diphenylphosphide (10), - react with sodium in liquid ammonia to give the phosphines (12). 

Similar findings were obtained with the combinations of selected ditertiary phosphines and mono- or difunctional alkynes.7... 

The (alkenyl-ethynyl)gold(i) complexes shown in Scheme 13 were prepared with mono- and ditertiary phosphine ligands and used as substrates for the coordination of coinage metal cations. The products are strongly luminescent.60... 

Similarly, secondary phosphines and a,a -dibromo-m-xylene usually react to give diprotonated ditertiary diphosphines [44-48]. However, in the case of the fluorous secondary phosphine 12-Rfs (Scheme 2, bottom), dialkylation occurred to give the metacyclophane 13-Rfs. As detailed elsewhere [40], extensive efforts to adjust the stoichiometry to favor noncyclized products failed. Fortunately, the reduction of 13-Rfs with IiAlH4 gave some of the target ligand lO-Rfs. 

Displacement reactions have been carried out in liquid ammonia (—33 °C) with R3P, R3As, R3Sb, ditertiary phosphines, bipy and phen22 leading to complete substitution of CN groups (equations 4-6). 

Table 65 Selected Complexes With Ditertiary Phosphines and Arsines...

An interesting ligand effect is found by changing the ditertiary phosphine. The complex... 

Myocardial imaging under II Cation uptake in myocardium Chelating ditertiary phosphine or 20, 613, 614... 

Controlling the Number of Metal Sites to which a Ditertiary Phosphine is Coordinated in Group VI Metal Carbonyls Limitations... 

It was only in a 1974 report (83) that some evidence was provided for the possible existence of pentamethylniobium through the isolation of its addition compounds with a ditertiary phosphine and with methyllithium. These compounds were synthesized according to the following scheme ... 

Chelatingbidentate ligands such as l,2-bis(diphenylphosphino)ethane-(diphos)152,191 cis-l,2-bis(diphenylphosphino)ethylene152 and 2,2 -bipyridyl(bipy)197) replace two moles of CO. In the reaction of the ditertiary phosphines (L) and Fe(CO)2cp(Sime3) there was some evidence for production of bridged derivatives of the type [(R3Si)cp(CO)Fe]2L154l Diphos and two... 

J. Chatt, and J. M. Davidson, The Tautomerism of Arene and Ditertiary Phosphine Complexes of Ruthenium(O), and the Preparation of New Types of Hydrido-Complexes of Ruthenium(II), J. Chem. Soc. 1965, 843-855. 

Trans-bromo structures are also found in the similar ditertiary phosphine bidentate complex [MnBr2(dmpe)2] (dmpe = l,2-bis(dimethylphosphino)ethane) 28 the Mn—P bond length in this compound (2.655 A) being comparable with that found in [MnCl2(diphos)2] (2.625 A). The reaction of [MnBr2(dmpe)] with LiAlH4 yields a Mn1 compound of stoichiometry Mn(AlH4)(dmpe)2 (Section 41.2.4). 

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