Dynamic 1H NMR studies of hindered internal rotations in the synthesized particular phosphorus ylide: Experimental and theoretical approaches

• Two rotational isomers of the synthesized ylide indicated experimentally.
• The barriers around the selected bonds are obtained by the dynamic 1H NMR.
• DFT and ab initio methods are performed.
• The calculated barriers confirmed the experimental data.

Dynamic 1H NMR measurements were performed within the synthesized particular phosphorus ylide involving 4-formylphenyl phenylcarbamate. Four rotational process and thereby parameters were targeted for rotation around the CC, C-C, HCNC and OCNC bonds. The Gibbs free activation energy in CDCl3, ΔG≠exp, was found to be 64 ± 2, 50 ± 2, 41 ± 2 and 63 ± 2, respectively. These findings were compared with related ab initio and DFT results on simulated situation. Theoretical methods tested, were comparable to the present D 1H NMR data.

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