RESTRICTED LIGAND MOTION IN TRANSITIONAL METAL-COMPLEXES .15. DYNAMIC BEHAVIOR OF TETRACARBONYL-ETA-DIEN-CHROM(0)-COMPLEXES

Date

1982-01-01

Author

KOTZIAN, M
KREITER, CG
Özkar, Saim

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Tetracarbonyl-η-dienechromium(O) complexes (diene  1,3-butadiene (I), trans-1,3-pentadiene (II), 2-methyl-1,3-butadiene (III), trans,trans-2,4-hexadiene (IV), 2-methyl-1,3-pentadiene (V), 2-ethyl-1,3-butadiene (VI), 2,4-pentadienoic acid methylester (VII), 2,4-hexadienoic acid methylester (VIII), 1,3-cyclohexadiene (IX) and 1,5-cyclooctadiene (X)) have been prepared photochemically and studied by 1H and 13C NMR spectroscopy. The 13C carbonyl ligand signals of I–VIII were found to be temperature dependent, indicating hindered ligand mobility of the formally octahedral complexes. The activation barriers were found to lie between 39–47 kj mol−1. IX and X differ markedly from I–VIII. The spectroscopic results can for IX be explained from rapid ligand movement even at 190 K, but X shows no ligand movement up to 345 K.

URI

https://hdl.handle.net/11511/70012

Journal

JOURNAL OF ORGANOMETALLIC CHEMISTRY

DOI

https://doi.org/10.1016/s0022-328x(00)89114-7

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Department of Chemistry, Article

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Citation Formats

M. KOTZIAN, C. KREITER, and S. Özkar, “RESTRICTED LIGAND MOTION IN TRANSITIONAL METAL-COMPLEXES .15. DYNAMIC BEHAVIOR OF TETRACARBONYL-ETA-DIEN-CHROM(0)-COMPLEXES,” JOURNAL OF ORGANOMETALLIC CHEMISTRY, pp. 29–42, 1982, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/70012.