Ferrocene derivatives mass spectrometry

Ferrocene can be polylithiated, by treatment with several equivalents of n-butyllithium in hexane-benzene solvent at 100° or in the presence of a chelating tertiary diamine (TMED). Addition of trimethylchlorosilane to the product so obtained affords a mixture containing FeC10H10-B (SiMe3) (n = 1-7) compounds. The tetrakis derivative (n = 4) was isolated as a pure substance other members of the series were identified only by gas chromatography and mass spectrometry (65). 

Low-voltage mass spectrometry has been used to identify ferrocene and its derivatives, for by using an ionizing voltage of 8 eV only the molecular ion peaks are observed (44,189). Reed and Tabrizi studied the mass spectra... 

Mass spectrometry has been used as a means of identification of various ferrocene derivatives, as well as in the study of specific problems such as determination of configuration and the interesting loss of formaldehyde in some methyl esters. 

Schlogl has used mass spectrometry to confirm the molecular weights of ferrocene derivatives such as... 

The spectra of various disubstituted ferrocenes were examined by Clancy and Spilners (44) at low ionizing voltage, and they observed only the molecular ions. They have also used mass spectrometry to identify products from the reaction of lithioferrocene with benzyl chloride one of the products was dibenzylferrocene (189). The mass spectra of [5]-ferroceno-phanes show very intense molecular ion peaks and fragmentation is limited (9, 10). The ketone derivatives (LXXXT) and (LXXXII) fragment by elimination of carbonyl groups first. 

Derivatives for electrospray ionization mass spectrometry. To enhance the range of analytes that are suitable, neutral derivatives of ferrocene have been examined these were designed to be "elec-trochemically ionizable" and are therefore inherently compatible with the operation of the electrospray source. Ferrocenoyl carbamates of alkanols were prepared by reaction with ferrocenoyl azide which, on heating, forms the reactive isocyanate (van Berkel et al. 1998). 

Quirke, J. M. E. Van Berkel, G. J. Electrospray tandem mass spectrometry smdy of ferrocene carbamate ester derivatives of saturated primary, secondary, and tertiary alcohols. J. Mass Spectrom. 2001, 36, 179-187. 

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