Barriers to ring rotation in 1,1',4,4'-tetra-tert-butyluranocene and 1,1',3,3'-tetra-tert-butylferrocene

doi:https://doi.org/10.1021/ja00402a001

Title: Barriers to ring rotation in 1,1',4,4'-tetra-tert-butyluranocene and 1,1',3,3'-tetra-tert-butylferrocene

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Abstract

The /sup 1/H NMR spectra of 1,1',4,4'-tetra-tert-butyluranocene show a singlet for the tert-butyl protons and three singlets for the ring protons. Coalescence occurs at -65 to -85/sup 0/C with splitting of each peak at lower temperatures, corresponding to ..delta..G/sup + +/ of rotation of 8.3 kcal mol/sup -1/. Coalescence was also observed for 1,1'3,3'-tetra-tert-butylferrocene and a corresponding ..delta..G/sup + +/ = 13.1 kcal mol/sup -1/ was obtained. 4 figures, 2 tables.

Authors:: Luke, W D; Streitwieser, A Jr

Publication Date:: 1981-06-17

Research Org.:: Univ. of California, Berkeley

OSTI Identifier:: 6394344

DOE Contract Number:: W-7405-ENG-48

Resource Type:: Journal Article

Journal Name:: J. Am. Chem. Soc.; (United States)

Additional Journal Information:: Journal Volume: 103:12

Country of Publication:: United States

Language:: English

Subject:: 38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY; IRON COMPLEXES; ROTATIONAL STATES; URANIUM COMPLEXES; COALESCENCE; EXPERIMENTAL DATA; FERROCENE; LOW TEMPERATURE; NUCLEAR MAGNETIC RESONANCE; TEMPERATURE DEPENDENCE; ACTINIDE COMPLEXES; COMPLEXES; DATA; DIENES; ENERGY LEVELS; EXCITED STATES; HYDROCARBONS; INFORMATION; MAGNETIC RESONANCE; NUMERICAL DATA; ORGANIC COMPOUNDS; POLYENES; RESONANCE; TRANSITION ELEMENT COMPLEXES; 400702* - Radiochemistry & Nuclear Chemistry- Properties of Radioactive Materials

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                    Luke, W D, and Streitwieser, A Jr. Barriers to ring rotation in 1,1',4,4'-tetra-tert-butyluranocene and 1,1',3,3'-tetra-tert-butylferrocene.  United States: N. p., 1981. 
        Web.  doi:10.1021/ja00402a001.

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                    Luke, W D, & Streitwieser, A Jr. Barriers to ring rotation in 1,1',4,4'-tetra-tert-butyluranocene and 1,1',3,3'-tetra-tert-butylferrocene.  United States.  https://doi.org/10.1021/ja00402a001

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                    Luke, W D, and Streitwieser, A Jr. Wed .  
        "Barriers to ring rotation in 1,1',4,4'-tetra-tert-butyluranocene and 1,1',3,3'-tetra-tert-butylferrocene".  United States.  https://doi.org/10.1021/ja00402a001.

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@article{osti_6394344,

  title        = {Barriers to ring rotation in 1,1',4,4'-tetra-tert-butyluranocene and 1,1',3,3'-tetra-tert-butylferrocene},

  author       = {Luke, W D and Streitwieser, A Jr},

  abstractNote = {The /sup 1/H NMR spectra of 1,1',4,4'-tetra-tert-butyluranocene show a singlet for the tert-butyl protons and three singlets for the ring protons. Coalescence occurs at -65 to -85/sup 0/C with splitting of each peak at lower temperatures, corresponding to ..delta..G/sup + +/ of rotation of 8.3 kcal mol/sup -1/. Coalescence was also observed for 1,1'3,3'-tetra-tert-butylferrocene and a corresponding ..delta..G/sup + +/ = 13.1 kcal mol/sup -1/ was obtained. 4 figures, 2 tables.},

  doi          = {10.1021/ja00402a001},

  url          = {https://www.osti.gov/biblio/6394344},
  journal      = {J. Am. Chem. Soc.; (United States)},
number       = ,

  volume       = 103:12,

  place        = {United States},

  year         = {1981},

  month        = {6}

}

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Barriers to ring rotation in 1,1',4,4'-tetra-tert-butyluranocene and 1,1',3,3'-tetra-tert-butylferrocene

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The ¹H-NMR spectra of 1,1',4,4'-tetra-tert-butyluranocene show a singlet for the tert-butyl protons and three singlets for the ring protons. Coalescence occurs at -65 to -85°C with splitting of each peak at lower temperatures, corresponding to ΔG* of rotation of 8.3 Kcal mol ^-1. Also, coalescence was also observed for 1,1',3,3'-tetra-tert-butylferrocene and a corresponding ΔG* = 13.1 Kcal mol ^-1 was obtained.
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