Iron compounds tetrafluoroborate

Bis[iV,iV -di(2-pyridyl)-imidazol-2-ylidene]aurate(I) tetrafluoroborates, preparation, 2, 292-293 Bis[iV,iV -di(2-pyridyl-methyl)-imidazol-2-ylidene]aurate(I) tetrafluoroborates, preparation, 2, 292-293 Bis(diselenolate) complexes, dinuclear iron compounds, 6, 242 Bis(dithiolene) compounds, in tungsten carbonyl and isocyanide complexes, 5, 644 Bis(enolato) complexes, with bis-Cp Ti(IV), 4, 589 Bis(enones), in reductive cyclizations, 10, 502 Bis(ethanethiolato) complexes, with bis-Cp Ti(IV), 4, 601 Bis(ethene)iridium complexes, preparation, 7, 328-329 -Bis(fluorenyl)zirconocene dichlorides, preparation,... 

Nucleophiles attack many dienyl compounds to give diene derivatives. Most such reactions are known for iron compounds. Thus, the reaction of (l,3-cyclohexadiene)tri-carbonyliron(O) with trityl tetrafluoroborate affords (cyclohexadienyl)tricarbonyliron cation, which reacts with a nucleophile forming a diene complex [equation (8.24)]. The... 

Compounds containing fluorine and chlorine are also donors to BF3. Aqueous fluoroboric acid and the tetrafluoroborates of metals, nonmetals, and organic radicals represent a large class of compounds in which the fluoride ion is coordinating with trifluoroborane. Representative examples of these compounds are given in Table 5. Coordination compounds of boron trifluoride with the chlorides of sodium, aluminum, iron, copper, 2inc, tin, and lead have been indicated (53) they are probably chlorotrifluoroborates. 

Notable examples of general synthetic procedures in Volume 47 include the synthesis of aromatic aldehydes (from dichloro-methyl methyl ether), aliphatic aldehydes (from alkyl halides and trimethylamine oxide and by oxidation of alcohols using dimethyl sulfoxide, dicyclohexylcarbodiimide, and pyridinum trifluoro-acetate the latter method is particularly useful since the conditions are so mild), carbethoxycycloalkanones (from sodium hydride, diethyl carbonate, and the cycloalkanone), m-dialkylbenzenes (from the />-isomer by isomerization with hydrogen fluoride and boron trifluoride), and the deamination of amines (by conversion to the nitrosoamide and thermolysis to the ester). Other general methods are represented by the synthesis of 1 J-difluoroolefins (from sodium chlorodifluoroacetate, triphenyl phosphine, and an aldehyde or ketone), the nitration of aromatic rings (with ni-tronium tetrafluoroborate), the reductive methylation of aromatic nitro compounds (with formaldehyde and hydrogen), the synthesis of dialkyl ketones (from carboxylic acids and iron powder), and the preparation of 1-substituted cyclopropanols (from the condensation of a 1,3-dichloro-2-propanol derivative and ethyl-... 

In the mixed valence BFD salts (in addition to the TCNQ compound, the picrate and tetrafluoroborate were also studied), the metal-metal interactions are so strong [Class III in the classification of Robin and Day (23)] that the metals are equivalent in every measurable respect. The doubly oxidized (24) Fe(III)-Fe(III) species is diamagnetic which is further evidence for strong interactions. Since the irons in BFD are 3.98 A apart (25), direct metal-metal interactions are not likely. We must then assume that in this case there exist metal-ligand-metal interactions of the magniture in which we are interested. We propose that the BFD system be considered a delocalized aromatic species. 

Only about 6% of the produced nickel is applied for the production of nickel compounds. An important one is nickel hydroxide [Ni(OH)2], which is used for nickel-cadmium and nickel-iron batteries. For the production of catalysts the hydroxide, nitrate, sulfate, formate, and carbonate of Ni are used. In the pigment industry nickel oxide, hydroxide, and phosphate are applied and for electroplating nickel sulfate, sulfamate, and tetrafluoroborate are used. 

Shortly afterwards, in 1960, Fischer discovered that addition of triphenyl-carbenium tetrafluoroborate to T -cyclohexa- 1,3-diene iron tricarbonyl 4 produced the novel in -cyclohexadienyl iron tricarbonyl cation 5 as a stable salt, and the reactivity of such compounds towards C-C bond formation was soon being explored. The application of organometallic complexes to organic synthesis had begun. 

The reactions of various iron carbonyl complexes, such as Fe(GO)4(NMe3), with allene compounds under photo-lytic conditions, yield chelated 77 -allyliron complexes. Two brief reviews discussing the chemistry and application to organic synthesis of these (7r-allyl)tricarbonyl iron lactone complexes have appeared recently. Reaction of the iron lactone complexes with trimethyloxonium tetrafluoroborate yields the carbene complex 23 in good yields. Treatment of the cationic carbene complex with triphenylphosphine results in substitution at the terminal end of the allyl ligand of the trimethylenemethane complex 24. 

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