Nuclear Magnetic Resonance Shift Reagents: Abnormal C Shifts Produced by Complexation of Lanthanide Chelates with Saturated Amines and n-Butyl Isocyanide.
Lanthanide-induced shfits of (13)C nuclear magnetic resonances are reported for several amines and n-butyl isocyanide. Contact contributions to such shifts, especially of beta carbons, are clearly important for the chelates of Eu(+3) and Pr(+3). The importance of contact terms is shown to change in a rather predictable manner with the structure of the amine.
Marzin
C
C
Gates and Crellin Laboratories of Chemistry, California Institute of Technology, Pasadena, Calif. 91109.
Leibfritz
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D
Hawkes
G E
GE
Roberts
J D
JD