Ferrocene acid chloride

Reaction of ferrocene acid chloride with appropriate diols in pyridine, with a catalytic amount of (dimethylamino)pyridine (DMAP), gave the corresponding ferrocene alcohol compounds. Formation of bis (ferrocene) compounds was minimized by working at high dilution with a 3-fold excess of diol. The ferrocene alcohols... 

Ferrocene carboxylic acid [1271-42-7] M 230.1, m 210°(dec), 225-230°(dec). Yellow crystals from pet ether. Also crystd from aqueous ethanol. [Matsue et al. J Am Chem Soc 107 3411 1985.] Acid chloride m 49° crystallises from pentane, Xmax 458nm [J Org Chem 24 280 1959], Methyl ester crystallises from aq MeOH m 70-71°. Anhydride m 143-145° from pet ether [J Org Chem 24 1487 7959]. Amide m 168-170° from CHCl3-Et20 or m 167-169° from C6H6-MeOH. [J Am Chem Soc 77 6295 1955 76 4025 7954.]... 

The chlorinated intermediate 255 is eliminated and cycloadds to Cjq, yielding pyrazo-linofullerenes of the structure 257 (Scheme 4.42). The 4-nitrophenyl-group can be replaced by a 4-methoxyphenyl- or a phenyl substituent. In this reaction various aromatics and substituted aromatics are tolerated as residues R (e.g. furan, ferrocene, pyrazole or benzene and substituted benzene). The nitro group of the nitrophenyl residue can be reduced with Sn-HCl to the aniline derivative, which can be further functionalized by amide coupling with acid chlorides [311]. 

The sulfonic acids of these metallocenes can be converted to sulfonyl chlorides, sulfonamides, etc., by appropriate reagents. Reduction of ferrocene-sulfonyl chloride by lithium aluminum hydride produces the rapidly oxidized ferrocenethiol in quantitative yield (43). Both the sulfonic acid of cyclopentadienylmanganese tricarbonyl and the corresponding sulfinic acid (obtained by sodium sulfite reduction of the sulfonic acid) have been converted to sulfones (10). 

In other examples, compounds in which a metal atom is already coordinated in a molecule can be used as a comonomer in an addition polymerization. Two examples involve the ferrocenes discussed in Chapter 6. The vinyl ferrocene molecule is shown in 7.14, and a similar vinyl manganese complex in 7.15.30 An alternative approach involves condensation polymerization. For example, if the R group in the ferrocene unit shown in 7.16 contains a hydroxyl group, it can be copolymerized with a diacid chloride. If it is an acid chloride, it can be copolymerized with a diamine. (This type of polymer is called a heteroannular chain if only one of the rings in the repeat unit is in the backbone, the polymer is called homoannular.)7 Similarly, the titanium complex shown in 7.17 is copolymerized with diacids or diols.30 Numerous other examples involving ferrocenes are discussed in Chapter 6. 

Miscellaneous Ferroceno Heterocyclic Compounds Treatment of the acid chloride of S-ferrocenylmethylthioglyeolic acid with stannic chloride in methylene chloride at —70° gave l,2-(2-thia-4-oxotetramethylene)ferrocene (27).17 Reaction of 27 with Raney nickel led to ring opening and gave a mixture of l-methyl-2-ethyl-... 

Ferrocene,136 ferrocenecarboxaldehyde,137 and hydroxymethyl-and hydroxyethylferrocene138 have all been used to prepare various ferrocenylcarbohydrates. Ferrocenecarboxylic acid chloride and 1,3-O-methyleneglycerol139, 140 gave the ferrocenecarboxylate (163). 

A C-substituted product was formed on treating phenothiazine with ferrocene carboxylic acid chloride even in the absence of AICI3... 

Polycondensates 27 and 28 (Fig. 9-22), incorporating either the 1,3- or 1,1 -disubstituted ferrocene unit, were prepared by solution polymerisation. Polymers 27 [25] were obtained by reaction of the novel monomer 29 [25] (Fig. 9-23) with the desired bis(acid chloride) 31 (Fig. 9-23) in refluxing CH2CI2 in the presence of triethylamine. Polymers 28 [25] were prepared following the same procedure from bis-phenol 30 [16] (Fig. 9-23). 

Aminothiazole reacts with both ferrocenecarboxaldehyde and ferrocenecarboxylic acid chlorideto give the expected imine and amide, respectively. Ferrocenecarboxylic acid chloride also reacts with phenothiazine to give both N- and C-acetylation. Ferrocene-carboxaldehyde and rhodanine gave 134, while reaction of the thiosemicarbazone of ferrocenecarboxaldehyde with chloroacetic acid in acetic acid gave 135. ... 

Reaction of the acid chloride of furan-2-carboxylic acid with ferrocene in a Friedel-Crafts acylation gave the expected ketone. 

A commonly used intermediate in the synthesis of ferrocene-based catalysts is chlorocarbonylferrocene. Formation of this acid chloride from the corresponding acid is capricious and can often result in low yields. To circumvent these difficulties, recently, Rotello and co-workers have investigated the use of the corresponding acid fluoride as a synthetic intermediate (Scheme 69) <1999JOC3745>. 

The ferrocene derivative of PNA monomer 50 is prepared by the reaction of ferrocene carboxylic acid chloride with thymine-PNA methyl es-... 

Cyclopentadienyl complexes show aromatic properties. This is the origin of the names metallocenes, ferrocene, etc. For example, the Friedel-Crafts acylation proceeds very easily. Ferrocene is acylated 3.3 x 10 times faster than benzene. The acylating reagents are the organic acid chlorides and acid anhydrides. The reaction is catalyzed by the typical Friedel-Crafts catalysts BF3, AICI3, etc. 

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