Iron carbonyls structures

Fe—Fe bond can be assigned structures 201 or 202 based on spectral data. The other product of this reaction is 193 (R = r-Bu), however, it is produced in minor amounts. Complexes 199 (R = R = r-Bu, R = Ph, R = r-Bu) were obtained. Reaction of 146 (M = Mo, R = Ph, R = R = Ft, R = r" = Me) with (benzyli-deneacetone)iron carbonyl gives rise to the bimetallic complex 200 (M = Mo), which reacts further with the free phosphole to form the bimetallic heteronuclear sandwich 203. The preferable coordination of the molybdenum atom to the dienic system of the second phosphole nucleus is rather unusual. The molybdenum atom is believed to have a greater tendency to coordinate via the trivalent phosphorus atom than via the dienic system. 

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... 

Like nickelocene itself, this complex has 2 electrons more than the number expected using the electron-counting approach outlined in this article. Interestingly, the iron analog [(C5H5)sFe2], for which such a tripledecker structure appears appropriate on an electron count, has been detected in mass-spectroscopic studies on ferrocene 179) and on the cyclopentadienyl iron carbonyl tetramer [C5H5FeCO]4 136). 

X-Ray analysis of the red-orange crystalline thioacrolein complex 272, which is derived from the dimeric thioacrolein derivative by way of thermal elimination of carbon monoxide (Scheme 17), has revealed a structure with an essentially square FejSs array. Analogous reactions with iron carbonyls have been carried out by McCaskie et who used thiete 1,1-dioxide instead of thiete (Scheme 18). 

There are a number of amine-catalyzed carbonylation reactions which are catalyzed by cobalt carbonyl and iron carbonyl. It seems to me that these are insertion reactions of metal amides, where carbon monoxide is inserted and then some kind of a reduction or subsequent reaction gives the observed products, urea derivatives or carbamates in alcohols. We do not know the structure of the iron compound it is probably similar to the cobalt species shown. 

Perfluoroethylene was first thought to react with iron carbonyl to give the iron(O) olefin complex [Fe(CO)3(C2F4)2] 213). It has since been shown that the product is a heterocyclic derivative of iron(II) (structure XII) 150, 214) and not a true olefin complex. 

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-... 

Substituted cyclopentadienones react with iron carbonyls to form stable, diamagnetic 7r-co triplexes of the type [Fe(CO)3(cyclopentadienone)] (215). The proposed structure is shown in (XX). These complexes undergo reactions typical of metal carbonyls, e.g., displacement of carbon monoxide by tertiary phosphines, but the carbonyl group of the ligand does not show reactions characteristic of a keto-group. These complexes are also formed by interaction of acetylenes with iron carbonyls (see Section VI,C). Interaction of tetracyclone and Fe3(CO)i2 gives unstable complexes which contain the sandwich anion [Fe(tetracyclone)2]2 analogous to the anion (XXV) (215). 

Among the sulfur-bridged trinuclear iron carbonyls S2Fe3(CO)g (structure like [25]) has been prepared in a new way (52), and CO substitutions of this (52) and the... 

Tetraethylammoniumhis(tetracarbonyliron)bis(/i-tetracarbonyliron)dithal-late(2 — ), [Et4N]2[Tl2Fe4(CO)16], decomposes rapidly upon exposure to air and is soluble in MeOH, CH2C12, and most polar organic solvents. Its crystal structure shows it to be a weak dimer of [Tl Fe(CO)4 2] and it probably exists as the monomer in solution.15 IR (CH2C12, cm-1) 1985(m), and 1908(s). It may be oxidized or irradiated to yield higher nuclearity thallium-iron carbonyl compounds.14,15... 

Many complexes involving iron are known, mostly clusters containing iron carbonyl fragments, and reports for some come from the early years of metal cluster chemistry. Perhaps the simplest compound is PbFe(CO)4 , described originally in I960 (59) and later in more detail by Marks in 1978 (60). The structure is unknown although it is postulated to be oligomeric on the basis of infrared spectroscopic data. 

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. 

Only two diantimony-iron carbonyl clusters are known. Whitmire (775) has described the synthesis of [Fe3(CO)9 /r3-SbFe(CO)4 2]2 (134) from the reaction between NaSb03 and methanolic [Fe(CO)5j. The structure is similar to that of 132 except that in 132 only one bismuth carries an Fe(CO)4... 

Oxanorbomane, 2,3,5,6-tetrakis(methylene)-adduct with benzoquinone, 1, 414 7-Oxanorbomanes iron carbonyl complexes structure, 4, 550 l70 NMR, 4, 580, 581 photoelectron spectroscopy, 4, 586 structure, 4, 547 Oxapenams synthesis, 7, 353... 

Spectrum A of Fig. 11 was obtained when the reduced iron was cooled to room temperature and exposed to CO at a pressure of 10-3 mm. (14). The band at 5.10 t is attributed to CO in the linear structure, Fe—C=0. At higher CO pressures, 1 mm., a second band is observed at 4.95 u- This second band may be due to iron carbonyl or to a weakly chemisorbed form of linear CO. 

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