Improvement in 13C NMR Measurements of Ring-Substituted i^-Cyclopentadienyl Metal Complexes

z l.5 Time-consuming 13C N M R measurements o f sparingly soluble ring-substituted cyclopentadienyl metal complexes can be avoided if INEPT techniques are applied. In particular, polarization transfer based on long range 13C -'H couplings (V (13C 1H); n = 2, 3) can be used to observe 13C N M R signals o f quaternary ,3C nuclei, which are difficult to observe in normal 13C N M R spectra. The improvement in the signal-to-noise ratio enabled to observe satellites due to 77S e 13C and I25T e 13C couplings. Some typical ferrocene derivatives as well as ^5-cyclopentadienyl-manganeseand -rhenium tricarbonyl derivatives were selected to demonstrate that the recommended methods are independent o f the metal and o f the type o f ring substitu­ tion.