Organoiron reagents

See page 101, Section 2.3, for the iron catalyzed cross-coupling of RMgX and ArX. 

See page 1528, Section 22 page 1724, Section 2 and page 1801, Section 6, respectively. 

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A,ii, Cyclopentadienylirondicarbonyl (Fp) Compounds. A common organoiron reagent is cyclo-pentadienylbis(carbonyliron) (Fp, 711). " This derivative can be converted to an alkyl derivative (713, where R = alkyl) by reaction with an alkyl halide, or to the protio derivative (713, R = H) by reaction with an acid. The anionic reagent 712 is prepared by reaction of iron pentacarbonyl with the dimer of cyclopentadiene (710 - sec. 115.B) at 200°C to give the dimeric species 711. Treatment of 711 with base leads to loss of cyclopentadiene and formation of 712. A byproduct of this process is ferrocene (71 4) formed by extrusion of carbon monoxide from 711.595... 

A.iii. Sodium Tetracarbonyl Ferrate. An extremely useful organoiron reagent is sodium tetra-carbonyl ferrate [Na2Fe(CO)4], usually prepared by reduction of iron pentacarbonyl. The synthetic utility of this reagent lies in its ability to react with alkyl halides in a stepwise manner, including the reaction with two different alkyl halides, as reported independently by Cooke and by Collman and co-workers. - When sodium tetracarbonyl ferrate reacted with 1-bromooctane, a trigonal bipyramidal complex (715) was formed... 

Organoiron complexes as potential reagents in organic synthesis. (M. Rosenblum, Accounts Chem. Res., 1974, 7, 122). 

Helquist has focused efforts on developing synthetically useful cyclopropanation reagents based upon the use of stable organoiron compounds which may be regarded, at least formally, as direct precursors of reactive carbene complexes. Sulfonium derivatives 1 and alkenyl complexesi have proven to be... 

Several important characteristics of this reaction are shown. First, the nucleophilic addition can be reversible if complex 736 is heated. Second, the complex can be decomposed by reaction with iodine (to give 737) or by protonolysis (with trifluoroacetic acid, TFA) to give cyclohexadiene derivative 738. The reagents used to remove the metal are similar to those used with organoiron complexes (sec. 8.9.A). 

Triiron dodecacarbonyl is a precursor to a great variety of organoiron compounds. In this respect, it is frequently a superior reagent to iron pentacarbonyl. ... 

M. Rosenblum - Organoiron Complexes as Potential Reagents in Organic Synthesis, Acc. Chem. Res. 7,122,1974. 

It seems that transition metal-catalyzed C(sp )-H functionalization is partial to noble palladium catalysts. Virtually, in 2013, Nakamura and coworkers developed a Fe(lll)-catalyzed, 8-aminoquinolinyl auxiliary-assisted P-C(sp )-H arylation with organozinc reagent in the presence of organic halides as oxidant using (Scheme 1.17) [44]. The preliminary mechanistic study suggests an organoiron intermediate 6. In 2014, Gu and Ackerman developed Fe(acac)3-catalyzed... 

When Li-C bonds in di-hthio reagents 1 were transmetallated to Fe-C bonds by use of common and simple FeCls, the in situ generated organoiron intermediates showed different reactivity with that of di-hthio reagents 1. For example, di-hthio reagents 1 did not react with unactivated alkynes such as 4-octyne. However, in the presence... 

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