| Abstract
| - Tandem mass spectrometry was used in the analysis of Cu+-d-glucose complexes. The MIKE spectrum ofthese complexes generated by FAB shows that the loss of a water molecule is the most important spontaneousfragmentation, followed by a second dehydration or the loss of H2, whereas the metal ion Cu+ is nevereliminated. A theoretical survey of the potential energy surface, based on the use of density functional theoryapproaches, shows that the attachment of Cu+ to the different basic centers of glucose induces nonnegligiblebond activation phenomena within the sugar moiety. As a consequence, the cleavage of the C−O linkages ofthe six-membered ring leads to open complexes which are systematically much more stable than those inwhich the cyclic structure of the sugar is preserved. These significant stability differences reflect the preferenceof Cu+ to yield bisligated complexes in which the metal forms almost linear arrangements with two oxygenatoms of the neutral through the participation of sd hybrids. The Cu+ cation has a catalytic effect on thesering-opening mechanisms. Several pathways for the successive loss of two molecules of water can be envisagedwith the origin in the cyclic and the open glucose−Cu+ complexes. In general, the most stable product ionsare those formed by a spontaneous fragmentation of the most stable open structures.
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