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Iron carbonyls, Fe2

The dinuclear iron carbonyl Fe2(CO)9, incidentally, has no osmium counterpart Os2(CO)9, perhaps because one or more of the ligands therein would need to play a bridging role (an unsymmetrical, polar unbridged structure (CO)40sOs(CO)5 would be extremely unlikely). If Os2(CO)9 could be prepared, reference to Fig. 2 suggests that it would be expected to contain a metal-metal bond of enthalpy 81 kJmol and length 297 pm. Other predictions about further osmium carbonyls yet to be prepared are to be found elsewhere. ... [Pg.1088]

Triiron dodecacarbonyl has been obtained by three different methods the action of heat on the iron carbonyl Fe2(CO)9, oxidation of the anion HFe(CO)4 by various oxidizing agents, and treatment of iron pentacarbonyl with triethylamine followed by acidification of the reaction mixture. The method described below is based on the oxidation of the anion HFe(C0)4 with manganese dioxide. [Pg.193]

Iron carbonyls Fe2(CO)9 and Fe(CO)5 cleave the C —Br bond of tribromofluoro-methane to give the following carbyne complex. [Pg.306]

The treatment of iron carbonyls with aqueous or alcoholic alkali can, by varying the conditions, be used to produce a series of interconvertible carbonylate anions [HFe(CO)4] , [Fe(CO)4] ", [Fe2(CO)g]2-, [HFe3(CO) ]- and [Fe4(CO)i3]"". Of these the first has a distorted trigonal bipyrarmdal stracture with axial H, the second... [Pg.1105]

The dehydration of primary amides with hydrosilane catalyzed by iron carbonyl clusters, such as [Et3NH][HFe3(CO)n] and Fe2(CO)9, was achieved by Seller and coworkers in 2009 (Scheme 43) [145]. This reaction shows good functional group tolerance (e.g., such as aromatic, heteroaromatic, and aliphatic substrates). [Pg.59]

A synthetic application of the sonolysis of iron carbonyls is the preparation of useful ferrilactones. The alkenyl epoxides (2, R = H, Ph, 1-hexanyl) are smoothly converted to the corresponding ferrilactone complexes (3) on reaction with Fe2(CO)9 suspended in THF and sonicated at room temperature [53]. Such complexes undergo several synthetically useful transformations (Scheme 3.7) including oxidation with Ce(IV) as a route to P-lactone natural products or P-lactam antibiotics and reaction with CO to afford 5-lactones [54]. Somewhat surprisingly this reaction is efficient even in diethyl ether, a volatile solvent which delivers low cavitation energy. [Pg.89]

Reactions of PhC=CC=CPh with iron carbonyls [Fe(CO)s, Fe2(CO)9, or Fe3(CO)i2] give isomers of complexes Fe(CO)4 (diyne)2 (265), Fe2(CO)6 (diyne)2 (266), and Fe2(CO)7 (diyne)2 (267), to which structures analogous to those found for similar products obtained from C2Ph2 were ascribed all three isomers of the second complex were formed. The reactions of hexa-2,4-diyne and Fe(CO)s have been described in more detail. UV irradiation of mixtures of the two... [Pg.199]

The ease of oxidahon of the surface iron carbonyl species has been shown in the preparation of Fe/MCM-41 catalysts. A method of preparation with ultrasound that led to subcarbonyl confined species in the case of Cr, Mn or Co catalysts rendered Fe203 when Fe2(CO)9 was used as precursor [23]. [Pg.325]

The reaction of a-halogenoximes 126 with amidines in the presence of iron carbonyls gives imidazoles 127 in 31-79% yields. The reaction occurred via deoxygenation of 4H-1,2,5-oxadiazines by iron carbonyls (equation 55). Efficiency of carbonyls decreased in the following order Fe3(CO)i2 > Fe2(CO)9 > Fe(Co)5 . ... [Pg.251]

Olefins readily displace CO groups from the iron carbonyls, Fe(CO)5, Fe2(CO)9, and Fe3(CO)12, to form complexes in which a C C bond of the olefin takes the place of each displaced CO group, and by donating its ir-electrons preserves the formal inert gas electron configuration of the iron atom in the complex. Acrylonitrile is the only reported example of a monoolefin complexing with iron in this way, but many complexes of iron with polyolefins are known. [Pg.85]

Cyclo-octatetraene reacts with iron carbonyls to form complexes with the compositions [Fe(CO)3(C8H8)], [Fe2(CO)6(C8H8)], and [Fe2(CO)7(C8H8)] 152, 168, 180). Nakamura and Hagihara 166) report that the complex [Fe(CO)3(C8H8)] decolorizes bromine in carbon tetrachloride and shows absorption bands in its infrared spectrum at 699, 716, and 720 cm-1 due to cis-double bonds. They suggest structure (XVI) for this complex, i.e., the hydrocarbon retains its tub form in the complex. These results are con-... [Pg.89]

Another class of tetrairon tin compounds, described by Stone (67) and Fritchie (73), are derived from reactions between alkylchlorostannanes and iron carbonyl species. The latter report describes the structure of [Sn Fe2-(CO)8( t-SnMe2) 2], 61, which contains a central tetrahedral tin atom bonded to two Fe2(CO)8(/i-SnMe2) fragments. [Pg.121]

As alluded to earlier, we have amassed a large body of X-ray data for binuclear iron carbonyl complexes of the Fe2(CO)6(X)(PPh2) type where X represents a three-electron donor ligand. The P-31 chemical shifts for these compounds are tabulated with Fe-P-Fe angles in Table III and a plot of 8 vs. angle is shown in Figure 11. Although the correlation is by no means perfect there is an unmistakable increase in... [Pg.185]

Exclusive formation of silylstyrenes 76 is achieved when the reactions of styrene and 4-substituted styrenes with HSiEt3 are catalyzed by Fe3(CO)i2 or Fe2(CO)9100. Other iron-triad metal carbonyl clusters, Ru3(CO)i2 and Os3(CO)i2, are also highly active catalysts, but a trace amount of hydrosilylation product 77 is detected in the Ru-catalyzed reactions and the Os-catalyzed reactions are accompanied by 3-12% of 77 (equation 31)100. Mononuclear iron carbonyl, Fe(CO)5, is found to be inactive in this reaction100. [Pg.1714]

Other examples concern the interaction between iron carbonyles and potassium alkylthiolates that is accompanied by disproportionation. The anion radicals Fe2(CO)g, Fe3(CO)fi, Fe4(CO)i3, and Fe(CO)2 are formed (Belousov et al. 1987). The interaction of iron carbonyls Fe(CO)5, Fe2(CO)9, and Fe3(CO)i2 with (CH3)3NO occurs according to a one-electron redox-disproportionation scheme, giving rise to iron carbonyl anion radicals Fe2(CO)s Fe3(CO)n, l e3(CO)i2, and Fe4(CO)ii (Belousov Belousova 1999). [Pg.42]

In 1993, Murai s group examined the effectiveness of the iron-triad carbonyl complexes Fe(CO)5, Fe2(CO)9 and Fe3(CO)12 as catalysts for the reaction of styrene with triethylsilane [47]. Whereas Fe(CO)5 showed no catalytic activity, Fe2(CO)9 and Fe3(CO)12 formed selectively P-silylstyrene 57a and ethylbenzene 58. Interestingly, Fe3(CO)12 is the catalyst that exhibited the highest selectivity. This trinuclear iron carbonyl catalyst was also successfully applied in the reaction of different para-substituted styrenes with Et3SiH giving only the (E)-P-triethylstyrenes in 66-70% yield (Scheme 4.23). [Pg.137]

The work reported by Eaton and coworkers can be summarized as reactions where an allene system in conjugation with a further unsaturated functionality reacts with carbon monoxide in the presence of an iron-carbonyl complex such as Fe(CO)5 under photochemical and thermal conditions when Fe2(CO)9 is used. When diallenes are used (X=R2C=C, Scheme 9.24), five-membered carbocyclic products are obtained [51, 52], whereas when allenyl ketones (X = O) are applied, five-membered lactones are generated [53, 54]. The use of allenylimines (X = NR) leads to five-membered lactams under these conditions [55]. [Pg.256]

Reactions of iron carbonyls with CH5N(PF2)2 give products of the type [ RN(PF2)J nFe2(CO)9 2n which may be regarded as derivatives of Fe2(COV. Th following compounds of this type have been reported in previous papers ... [Pg.490]

Iron carbonyl complexes are easily prepared by the reaction of Fe2(CO)9 with a cyclic diazene. An excess of the diazene prevents the more favoured formation of binuclear compounds29 3°). Trans-diazenes like trans-dimethyldiazene3 or azo-... [Pg.111]

The mass spectra of some binuclear iron carbonyl complexes of the type (triene) Fe2(CO)g have been investigated 26>33b Reaction between... [Pg.103]

My co-worker J. Sedlmeier then held the view that the amine-containing iron carbonyl complexes were also ionic compounds (VII, 14, 21). Hence the compound Fe2(CO)4(en)3 (en= 1,2-ethylenediamine) was formulated as [Fe(en)3]2+[Fe(CO)4]2. Systematic investigations revealed that reactions of the iron carbonyls with other nitrogen and oxygen donors likewise involved valency disproportionation of the metal with concomitant formation of mono- and polynuclear carbonylferrates, viz., [Fe(CO)4]2, [Fe2(CO)8]2-, [Fe3(CO)n]2-. R. Werner (VII, 15, 17, 19, 20) even discovered and characterized compounds containing the tetranuclear anion [Fe4(CO)13]2, the first being that from pyridine and iron carbonyl, viz.,... [Pg.4]

More recently (49) the reactions of iron carbonyls with alkali hydroxides and with nitrogen and oxygen bases have been once again thoroughly examined, so that the absorption spectra in the visible region of [Fe(CO)4]2, [Fe2(CO)8]2, [Fe3(CO)i, ]2 , [I e4(CO) 3]2, and of the corresponding hydrogen anions have been studied. [Pg.11]


See other pages where Iron carbonyls, Fe2 is mentioned: [Pg.153]    [Pg.37]    [Pg.153]    [Pg.37]    [Pg.440]    [Pg.291]    [Pg.148]    [Pg.297]    [Pg.89]    [Pg.27]    [Pg.131]    [Pg.207]    [Pg.433]    [Pg.91]    [Pg.24]    [Pg.112]    [Pg.113]    [Pg.251]    [Pg.73]    [Pg.472]    [Pg.440]    [Pg.665]    [Pg.84]    [Pg.292]    [Pg.278]    [Pg.122]    [Pg.112]   
See also in sourсe #XX -- [ Pg.8 , Pg.9 , Pg.178 ]

See also in sourсe #XX -- [ Pg.7 , Pg.8 , Pg.181 , Pg.193 , Pg.197 ]




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Carbonylation Iron carbonyl

Fe2

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