Fluorocarbon complex

The fluorocarbon complexes 56 are notably different in their chemical properties as compared to their hydrocarbon analogues 57. Complex 57a is extremely air sensitive and can only be isolated at low temperatures in... 

Metallocenes and related compounds for which mass spectral data have been reported are given in Tables I-XII, but in many cases only the molecular ion is reported. Metal carbonyls, nitrosyls and their derivatives, and fluorocarbon complexes are not discussed in this review, but Table XIX summarizes the compounds for which mass spectral data have been reported since Bruce s review (27). 

In the earliest authentic halocarbon complex (1982), o-diiodobenzene was found to chelate to cationic Ir(III) as shown in diagram (5)." An earlier proposed example proved to be misidentified when the crystal structure was carried out. To be stable, any such complex must resist oxidative addition, hence the use of an oxidation state, Ir(III), that is only oxidized with difficulty. The normally rather weakly basic halocarbon lone pairs are often reluctant to bind, but chelation and involvement of the least electronegative hahde, iodine, favor binding as does the cationic character of the complex. A series of such complexes was soon found, including complexes of fr(I)" and a series of weakly bound dichloromethane complexes for certain systems." These solvento complexes can be very labile and so find use as precursors for binding of other weakly basic hgands. Even fluorocarbon complexes proved viable." A review of the area is available. It now seems... 

For a discussion of these and related fluorocarbon complexes of transition metals the reader is referred to the chapter by Treichel and Stone in Volume I of this series. 

Many complexes in this class are known. Frequently they are analogous to hydrocarbon derivatives in their stoicheiometiy, but they are almost always much more stable thermally and to oxidation. The fluorocarbon complexes are usually prepared by rather different routes from those used for hydrocarbon complexes. 

Perfluorohydrocarbon-metal complexes are also more stable to reaction with oxygen than thdr hydrocarbon analogues. Other differences between M—Rf and M— R, complexes are the greater resistance of the former to cleavage reactions with acids, and the greater volatility of the fluorocarbon complexes. 

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