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Arene complexes, metal atom synthesis

The metal atom synthesis was first applied to the preparation of bis(arene)chromium derivatives by Timms. A wide range of complexes containing functional groups such as F, Cl, OMe and COOR were obtained. By introducing the arene in a solvent, compounds of relatively involatile ligands such as Cr(naphthalene)2 have been prepared. Green has extended the method to the synthesis of compounds such as TUC H ), Zr(C H )2PMe. Nb(C H )2 and... [Pg.313]

Co-condensation of Hf and Zr atoms from an electron-gun evaporation device, with P(Me)3 and arenes at 77K gave good yields of the species [M(arene)2P(Me3)]. Metal vapor synthesis led to Fe(i7 -arene)L2 and Fe(i7 -arene)-(i7 -diene), where L is a phosphorus ligand. In addition, complexes of stoichiometry Fe(T) -diene)L3 (where L is again a... [Pg.167]

The synthetic potential of transition metal atoms in organometallic chemistry was first demonstrated by the formation of dibenzenechrom-ium (127). Apart from chromium, Ti, V, Nb, Mo, W, Mn, and Fe atoms each form well-defined complexes with arenes on condensation at low temperatures. Interaction has also been observed between arenes and the vapors of Co, Ni, and some lanthanides. Most important, the synthesis of metal-arene complexes from metal vapors has been successful with a wide range of substituted benzenes, providing routes to many compounds inaccessible by conventional reductive preparations of metal-arene compounds. [Pg.72]

The Fischer-Hafner synthesis of sandwich compounds (33) does not permit functional groups to be incorporated into the arenes because of side reactions with the Lewis acid catalyst (Friedel-Crafts reducing conditions). This is not the case when metal atoms are used directly. Many metal-arene complexes have been identified that contain F, Cl, CH30, R2N and C02R substituents. It is reasonable to assume that polymer-bound phenyl substituents containing these functional groups will yield similar sandwich complexes. [Pg.248]

Alternatively, Mo(r -arene)2 complexes (arene = C HjCH, C HsF, C HjCl, C6H5(NMc2), CfjH5COOMe) have been prepared by metal atom vapor synthesis from molybdenum metal and arene [50,51]. [Pg.137]

The synthesis of stable tt-arene complexes of the transition metals has progressed substantially owing to metal atom chemistry. Particularly rewarding has been work on the production of bis(arene)metal(0) complexes of the early transition metals e.g., V, Cr, Mo and W yield bis(benzene)V(0), Cr(0), Mo(0) and W(0) complexes ". In addition, metal-atom reactions have yielded new arene-substituted compounds of V, Cr, Mo and W that cannot be prepared by classical methods . Hitherto unknown bis(arene)-metal(O) complexes can be prepared for Ti and Nb . The metal atom method is the most versatile (and often the only method) for the preparation of such complexes. Table 1 summarizes the bis(arene)metal(0) complexes prepared to date. [Pg.225]

Different stereochemical situations can arise during the synthesis of metal coordination compounds depending on the coordination geometries and the types of donor atoms or ligands coordinated to the metal center [22]. An enantiopure metal complex can be obtained through a stereoselective synthesis or by resolution of a racemic mixture. The first examples of tetracoordmated organometallic arene complexes that could be isolated as pure isomers were cyclopentadienyl half-sandwich diastereoisomers reported by Brunner and Schmidt [86-88]. [Pg.121]


See other pages where Arene complexes, metal atom synthesis is mentioned: [Pg.86]    [Pg.256]    [Pg.181]    [Pg.452]    [Pg.62]    [Pg.144]    [Pg.177]    [Pg.185]    [Pg.2620]    [Pg.2810]    [Pg.3521]    [Pg.4111]    [Pg.4918]    [Pg.4918]    [Pg.485]    [Pg.118]    [Pg.181]    [Pg.2619]    [Pg.2809]    [Pg.3520]    [Pg.4110]    [Pg.4917]    [Pg.4917]    [Pg.331]    [Pg.727]    [Pg.172]    [Pg.96]    [Pg.164]    [Pg.4]    [Pg.26]    [Pg.342]    [Pg.251]   
See also in sourсe #XX -- [ Pg.145 , Pg.146 , Pg.147 , Pg.148 ]

See also in sourсe #XX -- [ Pg.145 , Pg.146 , Pg.147 , Pg.148 ]




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Arene complexe

Arene complexes

Arene synthesis

Arenes complexes

Arenes metal complexes

Arenes metalation

Arenes metalations

Arenes metallation

Atomic complexities

Metal arene

Metal arenes

Metal atom syntheses

Metal complexes, synthesis

Metal-arene complexes

Metalated arenes

Metalation arene

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