Iron carbonyls complexes

6 Group VIII Iron, Ruthenium, and Osmium 6.1 Iron Carbonyl Complexes.- Stepwise degradation of S(NSiMe2)2 occurs on reaction with Fe (CO) 2 giving [Fe2(CO)g(Me SiNS)] 

The amino(methylene)phosphine (Me Si)2C=PN(SlMe )2 reacts with 

Sb-donor ligands occurs by heterolytic cleavage of the metal-metal — 121 bond and addition of ligand at the Fe(C0)2(N0) moiety. The 

Me2S2 in refluxing benzene gives the known syn- and anti-iscaners 

Dithioformate esters and 0-alkyl thioesters react with 

The organometalhc chemistry of iron has long been dominated by coordinahvely saturated carbonyl complexes [44]. Berthelot first synthesized Fe(CO)5 in 1891 [45]. Therefore it is, not surprising that early efforts in iron atalyzed olefin hydrogena-hon focused on Fe(CO)s, Fe2(CO)9 and related clusters [46]. This interest has continued for the past four decades. 

The proposed intermediacy of [Fe(CO)3], coupled with the high quantum efficiency observed with most mononuclear metal carbonyl complexes [54], inspired Schroeder and Wrighton to study photocatalytic olefin isomerization, hydrogenation and hydrosilylation reactions with Fe(CO)s [55], Irradiation of Fe(CO)s with near ultraviolet (Amax = 366nm) lightin the presence of excess 1-pentene furnished the thermodynamic mixture of cis and trons-2-pentene over the course of 2 h. From photolysis studies in neat olefin, it was estimated that each iron center produced 

The results of these studies also clearly ruled out the possibility of a binudear mechanism [58] and identified two distinct phases for the reaction. The first part of the process involves an induction period where the rate of the reaction increases, followed by a steady state period where the reaction rate decreases monotonicaUy as the system approaches equilibrium. Once equihbrium concentrations are established, addition of more 1-pentene with additional radiation proceeds without the induction period. These experiments also allowed estimation of the catalyst lifetime as 0.2 s. 

Subsequent studies by Hayes and Weitz [64] reported that addition of ethylene to (CO)3FeH2 or H2 to (CO)3Fe(Ti -CH2=CH2) yielded singlet (CO)3Fe(Ti -CH2=CH2) H2 based on observation of a strong infrared band near 2051 cm . Olefin insertion into an iron hydride followed by C-H reductive elimination yields ethane. The 

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Dinuclear iron carbonyl complexes with nitrogen containing bridges. A. N. Nesmeyanov, M. I. Rybinskaya and L. V, Rybin, Russ. Chem. Rev. (Engl. Transl.), 1979,48, 213-227 (123). 

Davis, M. 1. Speed, C. S. (1970) Gas-phase electron diffraction studies of some iron carbonyl complexes, J. Organomet. Chem. 21,401-413. 

Catenated Organic Compounds of the Group IV Elements, 4,1 Conjugate Addition of Grignard Reagents to Aromatic Systems, 1, 221 Cyclobutadiene Metal Complexes, 4, 95 Cyclopentadienyl Metal Compounds, 2, 365 Diene-Iron Carbonyl Complexes, 1, 1... 

An iron-catalyzed carbonylation reaction of alkynes 120 forming succinimides 121 by the aid of Fe(CO)5 78 or [Fe3(CO)i2] 119 has been reported by Beller et al. (Scheme 31) [94]. This reaction seems interesting as iron-carbonyl complexes are kinetically relatively inert. As a model system 3-hexyne was reacted with excess ammonia under 20 bar CO pressure. Employing a higher pressure leads to... 

With the low-valence iron pentacarbonyl, vinylcyclopropanes 22 are thermally transformed to the diene re-complexes, the (1,3-trans-pentadiene)iron carbonyl complexes 23, through bond fission, 1,2-hydrogen shift, and stereoselective coordination [15]. (Scheme 9)... 

TABLE 12. Reduction potentials of porphyrin-iron carbonyl complexes of germanium and tin in CH2CI2 with TBA(PF<5), 0.1 M, on Au electrodes vs SCEa... 

Table 7.12 Calculated BDEs De (Do) (kcal/mol) of iron carbonyl complexes with group-13 diyl ligands ER (E = B - Tl).a...

Syntheses of primary ally lie amines have been reviewed183. The regiochemistry of the reaction of iron carbonyl complexes with nucleophiles such as morpholine has been investigated. The (r 3-crolyl) Fe+(CO)4 BF4- complexes 172 (R1 = H R2 = Me or R1 = Me R2 = H) undergo preferential attack at the less substituted allyl terminus to yield allylic amines 173. The (/j2-crotyl acetate) Fe(CO)4 complex 174, on the other hand, does not react with morpholine184. 

The iron carbonyl complex [Fe(CO)5] in basic media hydrogenated steroidal dienes selectively (equations 10-12)30. 

Preparation of arylacetic acids using an iron carbonyl complex (Table 8.6)... 

Selected examples of the conversion of benzyl halides into arylacetic acids using iron carbonyl complexes... 

Although the reaction responsible for the generation of the hydride is not specified, it is assumed that it arises from a disproportionation of iron carbonyl complexes. The hydride presumably adds after ir-complexing to form the c-bonded complex which then splits out the metal hydride in either direction. The ir-complexed olefin may then be displaced by another olefin or undergo another hydride addition-elimination sequence. The second path involves olefin complexing with the deficient Fe(CO)3 species and formation of a jr-allyliron hydride intermediate ... 

Nonconjugated dienes are rearranged to iron carbonyl complexes of conjugated dienes when treated with FefCOjs or Fe3(CO)i2. Thus 1,4-pentadiene gives tmw -l,3-pentadieneiron tricarbonyl (34) possibly by the route ... 

The related iron carbonyl complex 55 was obtained by the reaction of [Fe3(CO)i2] with C(PPh3)(CO) however, according to [95] it is questionable because the spectroscopic data do not match with those of related compounds. The Mn and Re complexes [Cp(CO)2M C(PPh3)(CO) ] (M = Mn (56), Re (57)) have also been reported the ylide replaces the labile ether ligand in [Cp(CO)2M (OEt2)] [142]. The examples with the bonded ketenylidene ligand C(PPh3)(CO) are summarized in Fig. 30. 

A diene system with unsymmetrical 1,4-disubstitution is converted to the iron carbonyl complex 1 which is resolved into its enantiomers. The aldehyde function is conformationally locked in the transoid position and is diastereofacially shielded from the bottom face. Nucleophiles attack from the top face with high selectivity. Alternatively, chain elongation leads to the triene 2 which is reacted with diazomethane. Cerium(IV) oxidation removes the metal and furnishes the substituted cyclopropane 3. 

In addition to benzene and naphthalene derivatives, heteroaromatic compounds such as ferrocene[232, furan, thiophene, seienophene[233,234], and cyclobutadiene iron carbonyl complex[235] react with alkenes to give vinyl heterocycles. The ease of the reaction of styrene with substituted benzenes to give stilbene derivatives 260 increases in the order benzene < naphthalene < ferrocene < furan. The effect of substituents in this reaction is similar to that in the electrophilic aromatic substitution reactions[236]. 

The synthesis of metal-coordinated 1-azirines and the reactions of azirines induced by metals have opened a new area in the chemistry of this small ring heterocycle. Many of the reactions encountered bear resemblance to previously discussed thermally and photo-chemically induced reactions of 1-azirines. The reaction of a series of diiron enneacarbonyls in benzene results in coupling and insertion to give diimine complexes and ureadiiron complexes as well as pyrroles and ketones (76CC191). A mechanism for the formation of these products which involves initial 1,3-bond cleavage and generation of a nitrene-iron carbonyl complex as an intermediate was proposed. 

The filter cake and the distillate must be treated with nitric acid to decompose the contaminates of iron carbonyl complexes. This treatment should be done very carefully in a well-ventilated hood, because carbon monoxide is evolved vigorously. 

A review of diene-iron carbonyl complexes has recently appeared (5) metal complexes of di- and oligoolefinic ligands have also been reviewed (6). A general review of olefin, acetylenic, and 7r-allylic complexes of transition metals is due to Guy and Shaw (7). 

It is also relevant to record that several iron-carbonyl complexes with bridging, and in one case terminal, aryltellurol ligands have been prepared by reaction of Fe(CO)5, Fe(CO)12 or [ji-CpFe(CO)2]2 with diaryl ditellurides and which, together with complexes containing other transition metal carbonyls, e.g, ruthenium, osmium and manganese, provide a substantial number of interesting compounds.2... 

In other variations ketones are produced. The acyliron monoanion may be alkylated again with another alkyl halide to form a transient acyl-alkyl iron intermediate, which rapidly decomposes into ketone and the polynuclear iron carbonyl complex. This reaction is limited, however, because only very reactive alkylating agents such as methyl, allyl, and benzyl halides will react with the weakly nucleophilic acyliron monoanions ... 

It has been shown that the syn-tricyclooctadiene iron carbonyl complex 58 [Eq. (4)] readily undergoes stereospecific ring opening to afford the exo-bicyclooctatriene complex 59, and the anfi-tricyclooctadiene iron carbonyl... 

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... 

When various [Fe(heptafulvene)(CO)3] complexes are treated with POCI3 in DMF formylated products are produced.41 The reactivity of the iron carbonyl complex is markedly different than the reactivity of uncoordinated heptafulvenes which react with electrophiles to form the tropylium ion. 

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