Diiron enneacarbonyl

Pyrroles among other products are also formed from diiron enneacarbonyl or molybdenum carbonyl-induced decomposition of the Z-ketovinylazirine... 

A more complicated type of reaction leading to 2-styrylindoles is observed when 2-arylazirines are treated with the rhodium complexes,70 [(Ph3P)2 Rh(CO)Cl] or [Rh(CO)2Cl]2, or with dicobalt octacarbonyl71 (Scheme 42). In contrast, 2-arylazirines with molybdenum hexacarbonyl give pyrazines and dihydropyrazines, and with diiron enneacarbonyl give pyrroles (see Sections V,C,2 and IV,A,1, respectively). The use of relatively low molar ratios of 2-arylazirine to rhodium catalyst (2 1) causes the formation of 2,5-diarylpyrroles. 

Diarylthioketones are converted in good yields into orthometallated complexes by diiron enneacarbonyl.141 These in turn can be transformed oxidatively (Ce4+) or photochemically into isobenzothiophenes (see Section IV,C,2), or by reaction with mercuric trifluoroacetate into isobenzofurans (Scheme 78)142 the formation of methoxy esters is a competing process in... 

Diaryl thioketones are converted by diiron enneacarbonyl into products of orthometallation.141 Oxidative or photochemically induced deligation of these complexes provides an unusual and valuable synthetic entry into compounds in the uncommon isobenzothiophene category142,151 (Scheme 84). Moreover, the photochemical procedure provides the novel complex, (tetracyanoethylene)tetracarbonyl iron. The orthometallated complexes (68) can also be used to prepare isobenzofurans (see Section IV,B,5). 

Diiron enneacarbonyl, 50, 2J Diketones, from diazoketones and organoboranes, 53/ 82 3-DIKETONES FROM METHYL ALKYL KETONES 3-n-BUTYL-2,4-PENTANEDIONE, 51, 90 2,6-Dimethoxybenzaldehyde, by reduction of 2,6-dime thoxy-benzonitrile with Raney nickel alloy in formic acid,... 

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. 

Diiron nonacarbonyl is available from Alpha Inorganics, Inc., or Strem Chemicals, Inc. The submitters made the complex through photolysis of iron pentacarbonyl by the method of King.4 Procedures for preparation are also given by E. H. Braye and W. Hubei, Inorg. Syn., 8, 178 (1966), in which the name diiron enneacarbonyl is used. 

Thiobenzophenone can also serve as a C3S intermediate in the synthesis of some benzo[c]thiophenes. The carbon source in this case is carbon monoxide. Reaction of various thiobenzophenones with diiron enneacarbonyl in benzene at room temperature produced a complex, Ar2CSFe2(CO)6, which could be oxidized to form 2-hydroxy-5-aryl-benzo[c]thiophenes (226e) in 60-80% yield (73JA4905). 

Derivatives of diiron enneacarbonyl, Fe2(CO)9, in which two or three of the bridging carbonyls are replaced by diorganogermanium linkages adopt a structure based upon a trigonal bipyramid. This is exemplified... 

The reaction of Sn(r 1-Cp)2 with diiron enneacarbonyl produces bridging stannylene complexes (equation 128)298 304 305. 

Although nickel tetracarbonyl, iron pentacarbonyl, and diiron enneacarbonyl were already prepared in the 1890s, more than three decades passed before the chemistry of transition metal carbonyls took off. Undoubtedly, some parts of the chemical community had recognized that compounds such as Ni(CO)4 and Fe(CO)5 deserved special attention, in particular due to the use of Ni(CO)4 for the production of pure metallic nickel. However, since the structure of those compounds was unknown, transition metal carbonyls remained, more or less, a curiosity. 

Diiron enneacarbonyl reacted with 1 to give a host of products, the characterization of which was severly hampered by their instability. However, the complex, 24, was obtained in an indirect way as shown in eq. 50 (16). The IR spectrum of 24 shows three... 

Dihydromuscimol, GABA agonist, synthesis, 60, 297 Diimidazo[ 1,2-h 2, 1 -/Ipyridazine, bromination, 59, 329 Diiron enneacarbonyl, reaction with 1-azabuta-1,3-diene, 57, 6 Diisoquino[3,2-i 2, 3 -y)[3,8J-... 

In a well-ventilated hood a 500-ml. three-necked flask is immersed in an oil bath and fitted with a condenser and a mechanical stirrer a T-piece is inserted through a rubber stopper placed in the tfip of the condenser, one lead of the T-piecc being connected to a nitrogen supply and the other to a gas bubbler. ris-3,4-T)ichlorocyclobutene2, 20 g. (0.163 mole), and 125 ml. of anhydrous benzene are added to the flask and the apparatus is Hushed with nitrogen. Diiron enneacarbonyl, 25 g. (Note I) is I lieu added, the flow of N2 is stopped, and the mixture is heated to 50 55" with stirring. After about 15 minutes the in it ial rapid evolut ion of carbon monoxide becomes... 

M. Hidai Yuki Gosei Kagaku Kyokai Shi 27, 1117 (1969) Diiron enneacarbonyl 3 (6) Japan. 

Diiron enneacarbonyl, synthesis 46 Triiron dodecacarbonyl, synthesis 46 Tricarbonyl(cyclooctatetraene)iron, synthesis 47 Iron carbonyl complexes of triphenylphosphine, triphenyl-arsine, and triphenylstibine, synthesis 48 cis-Dinitrobis(ethylenediamine)cobalt(III) nitrite and nitrate, synthesis 60... 

Speyer and Wolf obtained diiron enneacarbonyl, Fe2(CO)9, by exposing an acetic acid solution of iron penta-carbonyl to sunlight. The yield of 30% claimed by these authors is reached only under the ideal conditions of bright sunshine and low temperatures. The modified procedure which is described here is based on the use of artificial light and water cooling of the reaction mixture it gives consistently high yields of diiron enneacarbonyl. 

Diiron enneacarbonyl is obtained as shiny orange hexagonal leaflets having a density of 2.08 g./cc. The com-... 

Cyclobutadiene-iron tricarbonyl is prepared through reaction of S,4-dichlorocydolmtene and diiron enneacarbonyl. In an analogous manner, one can prepare 1,2-diphenyl- 1,2,3,4-tetramethyl- and benzocyclobutadiene-iron tri-carbonyl complexes. Cyclobutadiene-iron tricarbonyl is aromatic" in the sense that it undergoes facile attack by electrophilic reagents to produce monosubstituted cydo-butadiene-iron tricarbonyl complexes. Functional groups in the substituents display many of their normal chemical reactions which can be used to prepare further types of substituted cyclobutadiene-iron tricarbonyl complexes. 

Keeley and Johnson 26°) observed an exceedingly small incorporation of 14CO in Fe2(CO)9 formed in the vapor photolysis of Fe(CO)s. They argued that electronically excited Fe(CO)s [Eq. (1)—(3)] should be the transient leading to diiron enneacarbonyl and not Fe(CO)4 which they considered to be very reactive towards exchange (Eq. (4)—(6)]. 

The first observed photochemical reaction with a metal carbonyl was the formation of diiron enneacarbonyl [Fea(CO)g] from Fe(CO)5 in Sunlight 134,135). 

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