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Iterative mass spectrometry and X-ray crystallography to study ion-trapping and rearrangements by a flexible cluster.

ABSTRACT: An important aspect of chemical reactions involves understanding the intermediate steps from reactants to products. The iterative use of mass spectrometry and X-Ray crystallography is demonstrated to be a powerful combination in this respect. We have applied them in identifying molecular clusters in solution followed by their solid-state structural characterizations. We used a key ligand, 2-[(2-hydroxy-3-methoxy-benzylidene)-amino]-ethanesulfonate (L), which serves as chelating/bridging units to stabilize the precursor [Li?Ni?(OH)?(L)?(CH?CN)?](ClO?)?·4CH?CN. The results of subsequent reactions witness a cascade of processes involving fragmentation, inner bridging ligand substitution (OH? to OCH??), changing modes of binding (chelate to monodentate) of the key ligand, ion-trapping and exchange (Li?, Na? and Ca²?) and their site preferences, coordinating and non-coordinating solvents (CH?CN to CH?OH, H?O and EtOH) replacement. The flexibility of the Ni?OL? species in solution permits the formation of six derivatives. The complimentary techniques open a broader prospect for cluster design and applications.

SUBMITTER: Zhang K

PROVIDER: S-EPMC3865461 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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