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The new preparative synthesis and the characterisation of l',l'-dibromo-1,2-methano[60]fullerene l a using a Seyferth reagent and the mass spectrometric evidence of the novel dumb-bell shaped molecular carbon allotropes C121 2 and ClZ2 3 obtained via a proposed intermediate C&: carbene generated from l a are reported.

An experimental comparison of product ion spectra produced by matrix-assisted laser desorption/ionization (MALDI) and electrospray ion-trap MS( n) for a group of small drug molecules is presented in this paper. The goal of the study was to demonstrate the usefulness of MALDI-MS with post-source decay (PSD) and collision-induced dissociation (CID) for the structural analysis of small drug molecules in the drug discovery process, where traditionally electrospray LC/MS methods are used. PSD and PSD/CID gave diverse product ions that were highly indicative of the structure of the drugs investigated (a group of 4-quinolone antibiotics and oleandomycin). In addition, the number of different product ions generated with MALDI-MS was always higher than with electrospray ion-trap MS( n) (with n < or =4) for the drug molecules studied. This investigation also showed that the choice of a suitable MALDI matrix for the analysis of low molecular weight compounds is quite important. It was found that of the three matrices examined, alpha-cyano-4-hydroxycinnamic acid (alpha-CHCA) produced the most intense fragmentation levels while TiO2, with its advantage of virtually no low mass background signals, did not generate quite the same amount of information.

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Due to their octahedral symmetry, otherwise not available for carbon based chemistry, hypervalent sulfur fluorides are very attractive as structural building blocks for functional organic materials. Direct fluorination offers a convenient access to multigram quantities of highly stable bis(4-nitrophenyl)tetrafluorosulfurane. Guided by molecular modeling, a novel catalytic process was devised to isomerize the predominantly formed cis isomer to the pure trans isomer.