Fluoroolefin complexes

Very strong metal-fluoroolefin bonding has also been inferred from preparative studies and the similarity of geminal 1 F-19F coupling constants in fluoroolefin complexes to those found in fluorinated cyclo-propanes (61, 85, 215). 

Stone et al. 43, 60, 61) have studied reactions of nickel and palladium isocyanides and a number of fluorocarbons which give a remarkable variety of products. With Ni(CNBu )4 and fluoroolefins [C2F4, (CF3)2C=C(CN)2 and CF2 = CFCF = CF2] themetallocyclic complexes (XXXIV), (XXXV), and (XXXVI) are observed 60,61) the complex Ni(CNBu )2(CjF5), analo-... 

In the last 27 years, tremendous progress has been made in this field of organic chemistry. Since the area is broad and the subject quite complex, no attempt has been made to present comprehensive coverage of the related literature. Instead, the authors of this review attempt to describe electrophilic reactions of fluoroolefins with particular stress on the mechanistic and synthetic aspects, to make it as comprehensive as possible in the main types of electrophilic reactions and to give the most important examples. Inevitably, this approach has left out some material and we offer in advance our regrets to all whose work was omitted. 

A chlorine substituent has a stabilizing effect on the allylic system. A stable complex of hexachloropropene and A1C13 known for a long time was found to be a salt of the pentachloroallyl cation [72]. Recently, the formation of long-lived allylic cations 28 and 29 in the reaction of SbF5 with corresponding chloro-fluoroolefins has been reported [73] ... 

By reaction of a 1,1-difluoroethene with tributylphosphane in the presence of boron trifluoride-diethyl ether complex, the vinylphosphonium salt is obtained. On subsequent hydrolysis the selectivity of formation of the Z- and F-isomer is 100%, but it diminishes after the introduction into the alkene. together with the perfluoroalkyl group, of substituents such as phenyl and 4-methoxyphcnyl. In accordance with this methodology, a method of substitution of fluorine by hydrogen at the fluoroolefinic double bond has been developed.194,206 The first stage of this reaction includes the formation of a fluoro-/5-phosphane from the fluoroalkene and tributylphosphane. The decomposition of this /l5-phosphane in the aqueous solvent leads to a fluoroalkene, e.g. formation of l.206... 

Chloro- (69, 70) and fluoroolefins (69, 250, 511) also have been observed to form stable complexes upon reaction with tetrakis(triphenyl-phosphine)platinum(O). These show no C=C stretching band in the... 

The reaction is reversible. If a fluorinated olefin is used, it would be expected that the resulting fluoroalkyl compound would be readily obtained, since the greater strength of the metal-fluorocarbon bond as compared to the metal-hydrocarbon bond favors the insertion reaction 267). The reaction of hydroplatinum(II) complexes with fluoroolefins has been extensively studied. A surprising product from a number of these reactions is a fluorovinyl compound rather than the anticipated fluoroalkyl complex. In Fig. 4 are shown the reactions of PtHCl(PEt3)2 with a series of fluoroolefins to give PtCl(CF=CF2)(PEt3)2 (XXXIV)... 

Photolysis of Au-alkyl complexes is synthetically useful, e.g., Au(CHj)L (L = PPhj, PPhjMe) in the presence of fluoroolefins such as C F, C F and CjFjCl leads to insertion products ... 

Refluxing Pt(PPh3)4 with activated olefins gives platinum(0)-olefin complexes with chloroolefins , fluoroolefins °, tetracyanoethylene and fumaronitrile ... 

Reactions of rhodium hydrido complexes with fluoroolefins give migration... 

Elements of this triad also afford complexes with fluoroolefins, for example [Fe(CO)4 (olefin)] (olefin = C2F4, C3F6, CCl2 = CF2, etc.), [RuL2(CO)2 (olefin)] (L = PR3, P(0R)3 olefin = C2F4, C3F,. ..). 

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