Cobalticinium-1,1 -dicarboxylic acid

Another important class of functionalized sandwich compounds that have been extensively used in the construction of hydrogen-bonded aggregates is that of the dicarboxylic acids of bis-benzene chromium and cobalticinium (see Table 3). 

A number of other triphenylantimony dichloride-derived products were recently tested for their ability to inhibit Balb 3T3 cells as a measnre of their ability as potential anticancer drugs [16]. This included those derived from cobalticinium-l,l -dicarboxylic acid nitrate and thiopyrimidine. These materials showed GI50 values of about 10 micrograms/m. 

In this manner benzil was converted to benzoic acid quantitatively and acenaphthene quinone was oxidized to naphthalene-1,8-dicarboxylic acid in 80% yield. Although these reactions are very facile and occur at a very low temperature (—50 to 15 °C) cobaltocene was irreversibly oxidized to a cobalticinium salt and a catalytic system was apparently not developed. 

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