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Published on: September 26, 2016
Synthesis, isomer count, and nuclear spin relaxation of H2O@open-C60 nitroxide derivatives
Yongjun Li1, Xuegong Lei, Ronald G Lawler
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
Abstract:
H(2)O@C(60) derivatives covalently linked to a nitroxide radical were synthesized. The (1)H NMR of the guest H(2)O revealed the formation of many isomers with broad signals. Reduction to the diamagnetic hydroxylamines sharpened the (1)H NMR signals considerably and allowed for an "isomer count" based on the number of observed distinct signals. For H(2)O@K-8, 17 positional isomeric nitroxides are predicted, not including additional numbers of regioisomers; indeed, 17 signals are observed in the (1)H NMR spectrum.
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