Solvation descriptors for ferrocene, and the estimation of some physicochemical and biochemical properties

Literature data on the solubility of ferrocene in nonaqueous solvents have been combined with the aqueous solubility to give partition coefficients from water to solvents, and have also been combined with the vapour pressure at 298 K to give gas-solvent partition coefficients. These two sets of partitions have been analysed through the solvation equations of Abraham to yield values of the solvation descriptors. Ferrocene is shown to have about the same dipolarity/polarisability and hydrogen bond basicity as naphthalene. From the solvation descriptors, various properties of ferrocene have been estimated, including the lipophilicity, the blood-brain distribution, and the vapour toxicity (as the nasal pungency threshold).