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Nonclassical complexes

The properties of the 7-norbornyl (18), 7-nobomenyl (19), and 7-norboma-dienyl (20) ions and radicals have aroused much interest in view of the evidence that the cations 19 and 20 have nonclassical -complex structures. We... [Pg.21]

Like most rules in bonding theory and structural chemistry, the 18-electron rule is often violated, even among the nonclassical complexes containing n acceptor ligands where, we have suggested, it should apply. Square planar complexes follow a 16-electron rule examples include Wilkinson s catalyst Rh(PPh3)3Cl (see also Section 9.8) and the vast number of square Pt(II) complexes. [Pg.314]

Nonclassical complexes of dihydrogen (page tv45) may be thought of as complexes in an arrested transition state and their existence provides strong support for a concerted reaction mechanism. Dioxygen, another nonpolar molecule, also adds reversibly to Vaska s complex, but in this case the X—Y bond is not completely broken. The bond Older of is reduced from two to essenlitilly one. [Pg.871]

The observed trends in pK with L variation in Table 9.1 are consistent with the trend that lower values of 1/2, i e., greater electron density at M, correspond to lower acidity. Thus the auxiliary ligand set plays a major role in determining acidities, as already noted above. For the [CpRuHjCPP)]system for both classical or nonclassical complexes, acidity increases with decreasing basicity of the diphosphines dmpe < dppp < 2PPh3 < dppe < dtfpe. Substitution of PPhj by CO decreases pX of related classical hydrides by 5-8 units [HCo(CO)4 and... [Pg.276]


See other pages where Nonclassical complexes is mentioned: [Pg.217]    [Pg.217]    [Pg.218]    [Pg.222]    [Pg.233]    [Pg.290]    [Pg.303]    [Pg.217]    [Pg.218]    [Pg.219]    [Pg.219]    [Pg.222]    [Pg.233]    [Pg.290]    [Pg.303]    [Pg.4389]    [Pg.195]    [Pg.163]    [Pg.276]    [Pg.4388]    [Pg.80]    [Pg.84]    [Pg.163]    [Pg.97]    [Pg.252]    [Pg.45]   
See also in sourсe #XX -- [ Pg.217 , Pg.218 , Pg.222 , Pg.233 , Pg.290 , Pg.303 ]

See also in sourсe #XX -- [ Pg.217 , Pg.218 , Pg.222 , Pg.233 , Pg.290 , Pg.303 ]




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Nonclassical

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