✍ Scribed by Nobuo Mori; Michiko Takamori
No coin nor oath required. For personal study only.
Relationships between molecular geometry and complexation effects in "C NMR spectra are reported for series of tricarbonyl(q6-[n]paracyclophane)chromium complexes and (q6-[n]paracyclophane) ($-cyclopentadienyl)iron(II) hexafluorophosphates, where n is 8, 9, 11, 12 and 15. In the Cr complex series in CDCI,, the complexation shift (As) for the aryl tertiary carbon increases with a decrease in n, from 34.5 (n = 15) to 37.9ppm ( n = 8 ) , whereas A6 for the aryl quaternary carbon decreases from 27.9 to 22.0ppm. Similar changes in A 1 1 6 with n are found in the Fe complex series, except that their A116 values are larger. This dependence of A6 on n is directly related to the interatomic distance between the metal and the ligand carbon. In addition, a significant geometry dependence of the complexation effects is observed for the benzylic-and the cyclopentadienyl-carbon resonances, but not for the one-bond aryl C-H spin-spin couplings.
📜 SIMILAR VOLUMES
## Abstract Internal rotation about the C‐2–C‐3 bond was observed in the ^13^C CP‐MAS NMR spectra of the solid complexes [M~2~(ηHC^1^C^2^C^3^Me~2~)(CO)~4~(ηC~5~H~5~)~2~]^+^ [BF~4~]^−^ where M = Mo or W.
Chiral synthons containing either 13Cor 15N-labelled glycine were prepared. The 13C and 15N NMR spectra of the Ni(II) complex of the Schi † base of (S)-2-(N-benzylprolyl)aminobenzophenone and 13C-1-, 13C-2or 15N-labelled glycine were measured and assigned. The observed splitting of the carbon signal