Ferrocenes reactions with

Ferrocene, reaction with bis(dimethyl-amino) methane to yield di-methylaminomethylferrocene, 40,31... 

The most notable chemistry of the biscylopen-tadienyls results from the aromaticity of the cyclopentadienyl rings. This is now far too extensively documented to be described in full but an outline of some of its manifestations is in Fig. 25.14. Ferrocene resists catalytic hydrogenation and does not undergo the typical reactions of conjugated dienes, such as the Diels-Alder reaction. Nor are direct nitration and halogenation possible because of oxidation to the ferricinium ion. However, Friedel-Crafts acylation as well as alkylation and metallation reactions, are readily effected. Indeed, electrophilic substitution of ferrocene occurs with such facility compared to, say, benzene (3 x 10 faster) that some explanation is called for. It has been suggested that. 

Hie necessity of an anionic tbiolale ligand was established by perforniing reactions with ferrocene tliioetliets 37 as ligands. Here, essentially racemic products... 

IrCl4(PMe2Ph)2 undergoes a redox reaction with ferrocene forming... 

RELATIVE REACTIVITIES OF REACTION OF FERROCENE DERIVATIVES WITH MeCOCl... 

Potassium cyanide, reaction with N,N-dimethylaminomethyl ferrocene methiodide to yield ferrocenyl-acetonitrile, 40, 45... 

The reaction with disubstituted formamides and phosphorus oxychloride, called the Vilsmeier or the Vilsmeier-Haack reaction,is the most common method for the formylation of aromatic rings. However, it is applicable only to active substrates, such as amines and phenols. An intramolecular version is also known.Aromatic hydrocarbons and heterocycles can also be formylated, but only if they are much more active than benzene (e.g., azulenes, ferrocenes). Though A-phenyl-A-methyl-formamide is a common reagent, other arylalkyl amides and dialkyl amides are also used. Phosgene (COCI2) has been used in place of POCI3. The reaction has also been carried out with other amides to give ketones (actually an example of 11-14),... 

The only other reaction with an aromatic substance is the C-H insertion into ferrocene [85], giving 41,which illustrates the highly electrophilic character of the phosphinidene complex. Other aromatic C-H insertions have been observed, but these likely occur by means of intermediate P,0- and P,N-ylids,such as the reaction of (0C)5W=PR withbenzophenone and azobenzene that give 42 and 43,respectively [56a, 86]. 

The synthesis of the unsymmetrical imidazolium salt 11 bearing a planar-chiral ferrocene was described by Bolm starting from (Rp)-[2-(trimethysilyl)-ferrocenyl] methanol 12 which afforded the salt in good yield after reaction with Ar,M-carbonyl diimidazole and methylation (Scheme 9) [18]. 

Togni and co-workers have used the convergent methodology to link phosphine-containing chiral ferrocene ligands on the cyclophosphazene core to obtain dendrimeric structures of the type 37 (Fig. 21) (201). The reaction with the cyclophosphazene end occurs by the replacement of the P-Cl bond and by the formation of the P-0 bond. The dendrimers contain twelve and sixteen ferrocene moieties respectively. The phosphine units present can coordinate to Rh(I) to afford metallic dendrimers, which have been shown to be excellent catalysts for the enantioselective hydrogenation of dimethyl itaconate. The product... 

These observations for Fe(Cp)2 in the presence of the polymer-bound Cr complex are consistent with Fe(Cp)2+, generated electrochemically, undergoing a reaction with Cr(CN-[P])c resulting in the chemical reduction of Fe(Cp)2+ and oxidation of the Cr species. Therefore, when the cathodic part of the Fe(Cp)2 /Fe(Cp)2+ wave is scanned, little ferricenium ion remains to be reduced electrochemically. As a result, the ferrocene molecule has effected the transfer of electrons from the polymer to the electrode. 

We now report a convenient method for the interfacial polycondensation of 1,1 -bis(3-aminoethyl)ferrocene (1) with a variety of diacid chlorides and diisocyanates, leading to ferrocene-containing polyamides and polyureas. In some instances, we have been able to observe film formation at the interface. Moreover, the polymerization reactions can be conveniently conducted at ambient temperatures in contrast to earlier high-temperature organometallic condensation... 

Table I. Polycondensation Reactions between 1,1 -Bis(6-amino-ethyl)ferrocene (1 and (6-hydroxyethyl)ferrocene (2) with Diacid Chlorides and Diisocyanates...

Evidence for slow inversion at nitrogen in the compound (106) and its tetrachloro analogue has been obtained 142>. The adduct of tetra-fluorobenzyne with cyclopentadiene has been obtained but of rather more interest is the isolation of the isomeric adducts (108) and (109) from the reaction of tetrafluorobenzyne with nickelocene 143>. No adducts were obtained from attempted reactions with ferrocene 144 80). 

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