Ferrocene-1,1’-dicarbonyl

An explosion occurred immediately after pouring and capping of the chloride recovered from preparation of ferrocene-1,1-dicarbonyl chloride. The storage bottle contained phosphoryl chloride recovered from similar preparations and which had been stored for some 3 months. No explanation was apparent. 

FIGURE 3 MiV -Bis-[3-pyiTole-l-yl)propyl)ferrocene-l,r-dicarboxamide, as pictured above, was prepared by reacting iV-(3-aminopropyl)pyrrole in the presence of triethylamine with ferrocene-1,1 -dicarbonyl chloride. 

Khan et al. recently polymerized 1,1 -ferrocene dicarbonyl chloride with various aromatic diamines in solution at low temperatures.183 The resulting polyaramides, 100, possessed glass transition temperatures above 350°C in the range of 360°-390°C and 10% decomposition temperatures between 300 and 430°C (Scheme 2.30). 

Some uses of sugars in novel resolutions of enantiomers have been reported. The ferrocene derivative 225 could be isolated from reaction of a mixture of d,l-and meso-isomers of the corresponding ferrocene dicarbonyl chloride with methyl 4,6-0-benzylidene-a-D-glucopyranoside. This could then be converted by methanolysis into the enantiomerically-pure (R,/ )-ferrocene derivative 226. When the chiral pyridinium salt 227 was photolysed, equimolar amounts of the diastereomers 228 and 229 were obtained. Although no chirality transfer occurred, the two isomers could be separated after acetylation, and some further chemistry was performed on the fused aziridine ring of one of the dia-... 

With tetracarbonyliron, mercury tetracarbonylferrate(II), ferrocene or dicarbonyl-cyclopentadienyliron, imidazole forms iron(II) complexes of the general form Fe(C3H3N2)2 or Fe(C3H3N2)2 0.5(C3H4N2). Iron(III) complexes have also been described. 

For the preparation of unsymmetrical ferrocenes, two ways by which only mono-substituted derivatives are produced have been suggested. One route starts from iron tetracarbonyl and a substituted cyclopenta-diene the other from monocyclopentadienyl iron dicarbonyl bromide, which on treatment with a substituted cyclopentadienyl lithium is finally converted into the corresponding mono-substituted ferrocene. Experience shows the first method to be more suitable for the preparation of aryl, and the latter method for the preparation of alkyl, derivatives (57). Corresponding work already carried out on substitution in Ru(C5H6)2 and Os CsH5)2 has also been fruitful. It is found that in the Friedel-Crafts reaction with acetyl or benzoyl chloride there is a distinct predominance of mono- over disubstitution as the atomic weight of the central atom increases (47, 72). 

Scheme 12.17 The synthesis of a series of novel ferrocene-oligomers 69-72 and polyferrocenyl peptide 73, after Boc-deprotection of l,n -bis(Boc-amino)ferrocene, it was coupled to ferrocene-1, /f -dicarbonyl chloride in THF, using the polycondensation protocol.

The first step is a simple displacement of two molecules of carbon monoxide. In the second step the acidic hydrogen of 7r-bonded cyclopentadiene shifts to the iron atom to give w-cyclopentadienyliron dicarbonyl hydride, a known compound. Two molecules of this iron hydride then add hydrogen to cyclopentadiene to form cyclopentene and the dimer of w-cyclopentadienyl-iron dicarbonyl. This reaction proceeds at temperatures between 150° and 220° C. Above 220° C, the remaining carbon monoxide molecules are displaced by a second molecule of cyclopentadiene forming ferrocene [42). 

Methylcyclopentadiene readily undergoes reaction with metal carbonyls 47) and even 1,3-diphenylcyclopentadiene reacts with iron carbonyl 4S). A novel method for obtaining a ferrocene with one substituted ring, is the reaction of 1,3-diphenylcyclopentadiene with the dimer of cyclopentadienyl-iron dicarbonyl at 170° C to produce 1,3-diphenylferrocene in 15% yield. Other substituted cyclopentadienes which have been used are tetraphenyl-cyclopentadienone in the preparation of tetraphenyl(hydroxy)cyclopenta-dienylmanganese tricarbonyl 49) and indene in the preparation of the dimer of indenylmolybdenum tricarbonyl (50). A variety of substituted fulvenes have been used in the preparation of substituted cyclopentadienyl metal tricarbonyl compounds of Cr, Mo, and W (57, 52). This latter reaction proceeds best in the presence of a solvent, such as 1,2-dimethoxyethane, to permit easy abstraction of hydrogen. 

C20H28Cr2 ,0P2 f Bis[(Tj -cyclopentadienyl)dicarbonyl(trimethyl phos-phite)chromium](Cr-Cr), 45B, 971 C2oH28FeSi4, 1,1 -Bis(pentamethyldisilanyl)ferrocene, 33B, 353 C2oH3oBr4lr2, Di-M-bromobis[bromo(T -pentamethylcyclopentadienyl)iridium], 45B, 971... 

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