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.
Gates and Crellin Laboratories of Chemistry, California Institute of Technology, Pasadena, Calif. 91109.
C
C
Marzin
D
D
Leibfritz
G E
GE
Hawkes
J D
JD
Roberts